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210 being erected so as to produce a rude resemblance to the figure of a sphinx, hence the name of the family. The protection is carried further by those species which retract the first three segments and have large ocelli on each side of the fourth segment, thus giving to the caterpillar, when the forepart of its body is elevated, the appearance of a snake in a threatening attitude.

The blood-red forked tentacle, thrown out of the neck of the larvæ of the genus Papilio when alarmed, is, no doubt, a protection against the attacks of ichneumons, and may, perhaps, also frighten small birds; and the habit of turning up the tail possessed by the harmless rove-beetles (Staphylinidæ), giving the idea that they can sting, has, probably, a similar use. Even an unusual angular form, like a crooked twig or inorganic substance, may be protective; as Mr. Poulton thinks is the case with the curious caterpillar of Notodonta ziezae, which, by means of a few slight protuberances on its body, is able to assume an angular and very unorganic-looking appearance. But perhaps the most perfect example of this kind of protection is exhibited by the large caterpillar of the Royal Persimmon moth (Bombyx regia), a native of the southern states of North America, and known there as the "Hickory-horned devil." It is a large green caterpillar, often six inches long, ornamented with an immense crown of orange-red tubercles, which, if disturbed, it erects and shakes from side to side in a very alarming manner. In its native country the negroes believe it to be as deadly as a rattlesnake, whereas it is perfectly innocuous. The green colour of the body suggests that its ancestors were once protectively coloured; but, growing too large to be effectually concealed, it acquired the habit of shaking its head about in order to frighten away its enemies, and ultimately developed the crown of tentacles as an addition to its terrifying powers. This species is beautifully figured in Abbott and Smith's Lepidopterous Insects of Georgia.

Besides those numerous insects which obtain protection through their resemblance to the natural objects among which they live, there are some whose disguise is not used for


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Rh concealment, but as a direct means of securing their prey by attracting them within the enemy's reach. Only a few cases of this kind of coloration have yet been observed, chiefly among spiders and mantidæ; but, no doubt, if attention were given to the subject in tropical countries, many more would be discovered. Mr. H. O. Forbes has described a most interesting example of this kind of simulation in Java. While pursuing a large butterfly through the jungle, he was stopped by a dense bush, on a leaf of which he observed one of the skipper butterflies sitting on a bird's dropping. "I had often," he says, "observed small Blues at rest on similar spots on the ground, and have wondered what such a refined and beautiful family as the Lycaenidæ could find to enjoy, in food apparently so incongruous for a butterfly. I approached with gentle steps, but ready net, to see if possible how the present species was engaged. It permitted me to get quite close, and even to seize it between my fingers; to my surprise, however, part of the body remained behind, adhering as I thought to the excreta. I looked closely, and finally touched with my finger the excreta to find if it were glutinous. To my delighted astonishment I found that my eyes had been most perfectly deceived, and that what seemed to be the excreta was a most artfully coloured spider, lying on its back with its feet crossed over and closely adpressed to the body." Mr. Forbes then goes on to describe the exact appearance of such excreta, and how the various parts of the spider are coloured to produce the imitation, even to the liquid portion which usually runs a little down the leaf. This is exactly imitated by a portion of the thin web which the spider first spins to secure himself firmly to the leaf; thus producing, as Mr. Forbes remarks, a living bait for butterflies and other insects so artfully contrived as to deceive a pair of human eyes, even when intently examining it.

A native species of spider (Thomisus citreus) exhibits a somewhat similar alluring protection by its close resemblance to buds of the wayfaring tree, Viburnum lantana. It is pure creamy-white, the abdomen exactly resembling in shape and colour the unopened buds of the flowers among which it takes

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212 its station; and it has been seen to capture flies which came to the flowers.

But the most curious and beautiful case of alluring protection is that of a wingless Mantis in India, which is so formed and coloured as to resemble a pink orchis or some other fantastic flower. The whole insect is of a bright pink colour, the large and oval abdomen looking like the labellum of an orchid. On each side, the two posterior legs have immensely dilated and flattened thighs which represent the petals of a flower, while the neck and forelegs imitate the upper sepal and column of an orchid. The insect rests motionless, in this symmetrical attitude, among bright green foliage, being of course very conspicuous, but so exactly resembling a flower that butterflies and other insects settle upon it and are instantly captured. It is a living trap, baited in the most alluring manner to catch the unwary flower-haunting insects.

The colours of birds' eggs have long been a difficulty on the theory of adaptive coloration, because, in so many cases it has not been easy to see what can be the use of the particular colours, which are often so bright and conspicuous that they seem intended to attract attention rather than to be concealed. A more careful consideration of the subject in all its bearings shows, however, that here too, in a great number of cases, we have examples of protective coloration. When, therefore, we cannot see the meaning of the colour, we may suppose that it has been protective in some ancestral form, and, not being hurtful, has persisted under changed conditions which rendered the protection needless.

We may divide all eggs, for our present purpose, into two


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Rh and such immeasurable possibilities—to the wisdom, foresight, and strength of purpose of Mr. Cecil Rhodes, the present Premier of the Cape Colony, is, I think, fully recognised in this country. The knowledge that many years of travel as a hunter and collector of natural history specimens had given me of the topographical features of the country, enabled me to play my part in the actual occupation of Mashunaland, and that I may yet live to see that far-off country, endeared to me by so many stirring reminiscences, grow and increase in prosperity until it has become a rich and prosperous portion of the British Empire, is my most earnest desire.

Some chapters of this book have already appeared in print in the shape of articles to the Field newspaper, and I have to thank the editor of that publication for his kindness in allowing me to reprint them here. My best thanks are also due to Messrs. Armour, Lodge, Whymper, and Wolf, for the care and trouble they have bestowed on the drawings depicting hunting scenes and phases of native life, with which the book is illustrated. The representations of hunting scenes and other incidents of adventure were all drawn from my own oral descriptions, and much care has been bestowed upon them. I am indebted to the kindness of the President and Council of the Royal Geographical Society for the map at the end of the book, which I hope will enable my readers to follow my routes; and also for some of the plates representing scenes on the Zambesi and in Mashunaland, which were originally produced by the Society to illustrate a paper written by myself, entitled "Twenty Years in Zambesi," which appeared in the


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Rh great divisions; those which are white or nearly so, and those which are distinctly coloured or spotted. Egg-shells being composed mainly of carbonate of lime, we may assume that the primitive colour of birds' eggs was white, a colour that prevails now among the other egg-bearing vertebrates—lizards, crocodiles, turtles, and snakes; and we might, therefore, expect that this colour would continue where its presence had no disadvantages. Now, as a matter of fact, we find that in all the groups of birds which lay their eggs in concealed places, whether in holes of trees or in the ground, or in domed or covered nests, the eggs are either pure white or of very pale uniform coloration. Such is the case with kingfishers, bee-eaters, penguins, and puffins, which nest in holes in the ground; with the great parrot family, the woodpeckers, the rollers, hoopoes, trogons, owls, and some others, which build in holes in trees or other concealed places; while martins, wrens, willow-warblers, and Australian finches, build domed or covered nests, and usually have white eggs.

There are, however, many other birds which lay their white eggs in open nests; and these afford some very interesting examples of the varied modes by which concealment may be obtained. All the duck tribe, the grebes, and the pheasants belong to this class; but these birds all have the habit of covering their eggs with dead leaves or other material whenever they leave the nest, so as effectually to conceal them. Other birds, as the short-eared owl, the goatsucker, the partridge, and some of the Australian ground pigeons, lay their white or pale eggs on the bare soil; but in these cases the birds themselves are protectively coloured, so that, when sitting, they are almost invisible; and they have the habit of sitting close and almost continuously, thus effectually concealing their eggs.

Pigeons and doves offer a very curious case of the protection of exposed eggs. They usually build very slight and loose nests of sticks and twigs, so open that light can be seen through them from below, while they are generally well concealed by foliage above. Their eggs are white and shining; yet it is a difficult matter to discover, from beneath, whether there are eggs in the nest or not, while they are well hidden by the thick foliage above. The Australian podargi—


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214 huge goatsuckers—build very similar nests, and their white eggs are protected in the same manner. Some large and powerful birds, as the swans, herons, pelicans, cormorants, and storks, lay white eggs in open nests; but they keep careful watch over them, and are able to drive away intruders. On the whole, then, we see that, while white eggs are conspicuous, and therefore especially liable to attack by egg-eating animals, they are concealed from observation in many and various ways. We may, therefore, assume that, in cases where there seems to be no such concealment, we are too ignorant of the whole of the conditions to form a correct judgment.

We now come to the large class of coloured or richly spotted eggs, and here we have a more difficult task, though many of them decidedly exhibit protective tints or markings. There are two birds which nest on sandy shores—the lesser tern and the ringed plover,—and both lay sand-coloured eggs, the former spotted so as to harmonise with coarse shingle, the latter minutely speckled like fine sand, which are the kinds of ground the two birds choose respectively for their nests. "The common sandpipers' eggs assimilate so closely with the tints around them as to make their discovery a matter of no small difficulty, as every oologist can testify who has searched for them. The pewits' eggs, dark in ground colour and boldly marked, are in strict harmony with the sober tints of moor and fallow, and on this circumstance alone their concealment and safety depend. The divers' eggs furnish another example of protective colour; they are generally laid close to the water's edge, amongst drift and shingle, where their dark tints and black spots conceal them by harmonising closely with surrounding objects. The snipes and the great army of sandpipers furnish innumerable instances of protectively coloured eggs. In all the instances given the sitting-bird invariably leaves the eggs uncovered when it quits them, and consequently their safety depends solely on the colours which adorn them." The wonderful range of colour and marking in the eggs of the guillemot may be imputed to the inaccessible rocks on which


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Rh it breeds, giving it complete protection from enemies. Thus the pale or bluish ground colour of the eggs of its allies, the auks and puffins, has become intensified and blotched and spotted in the most marvellous variety of patterns, owing to there being no selective agency to prevent individual variation having full sway.

The common black coot (Fulica atra) has eggs which are coloured in a specially protective manner. Dr. William Marshall writes, that it only breeds in certain localities where a large water reed (Phragmites arundinacea) abounds. The eggs of the coot are stained and spotted with black on a yellowish-gray ground, and the dead leaves of the reed are of the same colour, and are stained black by small parasitic fungi of the Uredo family; and these leaves form the bed on which the eggs are laid. The eggs and the leaves agree so closely in colour and markings that it is a difficult thing to distinguish the eggs at any distance. It is to be noted that the coot never covers up its eggs, as its ally the moor-hen usually does.

The beautiful blue or greenish eggs of the hedge-sparrow, the song-thrush, the blackbird, and the lesser redpole seem at first sight especially calculated to attract attention, but it is very doubtful whether they are really so conspicuous when seen at a little distance among their usual surroundings. For the nests of these birds are either in evergreens, as holly or ivy, or surrounded by the delicate green tints of our early spring vegetation, and may thus harmonise very well with the colours around them. The great majority of the eggs of our smaller birds are so spotted or streaked with brown or black on variously tinted grounds that, when lying in the shadow of the nest and surrounded by the many colours and tints of bark and moss, of purple buds and tender green or yellow foliage, with all the complex glittering lights and mottled shades produced among these by the spring sunshine and by sparkling raindrops, they must have a quite different aspect from that which they possess when we observe them torn from their natural surroundings. We have here, probably, a similar case of general protective harmony to that of the green caterpillars with beautiful white or purple bands and spots, which, though gaudily conspicuous when seen alone,


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 become practically invisible among the complex lights and shadows of the foliage they feed upon.

In the case of the cuckoo, which lays its eggs in the nests of a variety of other birds, the eggs themselves are subject to considerable variations of colour, the most common type, however, resembling those of the pipits, wagtails, or warblers, in whose nests they are most frequently laid. It also often lays in the nest of the hedge-sparrow, whose bright blue eggs are usually not at all nearly matched, although they are sometimes said to be so on the Continent. It is the opinion of many ornithologists that each female cuckoo lays the same coloured eggs, and that it usually chooses a nest the owners of which lay somewhat similar eggs, though this is by no means universally the case. Although birds which have cuckoos' eggs imposed upon them do not seem to neglect them on account of any difference of colour, yet they probably do so occasionally; and if, as seems probable, each bird's eggs are to some extent protected by their harmony of colour with their surroundings, the presence of a larger and very differently coloured egg in the nest might be dangerous, and lead to the destruction of the whole set. Those cuckoos, therefore, which most frequently placed their eggs among the kinds which they resembled, would in the long run leave most progeny, and thus the very frequent accord in colour might have been brought about.

Some writers have suggested that the varied colours of birds' eggs are primarily due to the effect of surrounding coloured objects on the female bird during the period preceding incubation; and have expended much ingenuity in suggesting the objects that may have caused the eggs of one bird to be blue, another brown, and another pink. But no evidence has been presented to prove that any effects whatever are produced by this cause, while there seems no difficulty in accounting for the facts by individual variability and the action of natural selection. The changes that occur in the conditions of existence of birds must sometimes render the concealment less perfect than it may once have been; and when any danger arises from this cause, it may be met either


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 by some change in the colour of the eggs, or in the structure or position of the nest, or by the increased care which the parents bestow upon the eggs. In this way the various divergences which now so often puzzle us may have arisen.

If we consider the habits and life-histories of those animals which are more or less gregarious, comprising a large proportion of the herbivora, some carnivora, and a considerable number of all orders of birds, we shall see that a means of ready recognition of its own kind, at a distance or during rapid motion, in the dusk of twilight or in partial cover, must be of the greatest advantage and often lead to the preservation of life. Animals of this kind will not usually receive a stranger into their midst. While they keep together they are generally safe from attack, but a solitary straggler becomes an easy prey to the enemy; it is, therefore, of the highest importance that, in such a case, the wanderer should have every facility for discovering its companions with certainty at any distance within the range of vision.

Some means of easy recognition must be of vital importance to the young and inexperienced of each flock, and it also enables the sexes to recognise their kind and thus avoid the evils of infertile crosses; and I am inclined to believe that its necessity has had a more widespread influence in determining the diversities of animal coloration than any other cause whatever. To it may probably be imputed the singular fact that, whereas bilateral symmetry of coloration is very frequently lost among domesticated animals, it almost universally prevails in a state of nature; for if the two sides of an animal were unlike, and the diversity of coloration among domestic animals occurred in a wild state, easy recognition would be impossible among numerous closely allied forms.


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 The wonderful diversity of colour and of marking that prevails, especially in birds and insects, may be due to the fact that one of the first needs of a new species would be, to keep separate from its nearest allies, and this could be most readily done by some easily seen external mark of difference. A few illustrations will serve to show how this principle acts in nature.

My attention was first called to the subject by a remark of Mr. Darwin's that, though, "the hare on her form is a familiar instance of concealment through colour, yet the principle partly fails in a closely allied species, the rabbit; for when running to its burrow it is made conspicuous to the sportsman, and no doubt to all beasts of prey, by its upturned white tail." But a little consideration of the habits of the animal will show that the white upturned tail is of the greatest value, and is really, as it has been termed by a writer in The Field, a "signal flag of danger." For the rabbit is usually a crepuscular animal, feeding soon after sunset or on moonlight nights. When disturbed or alarmed it makes for its burrow, and the white upturned tails of those in front serve as guides and signals to those more remote from home, to the young and the feeble; and thus each following the one or two before it, all are able with the least possible delay to regain a place of comparative safety. The apparent danger, therefore, becomes a most important means of security.

The same general principle enables us to understand the singular, and often conspicuous, markings on so many gregarious herbivora which are yet, on the whole, protectively coloured. Thus, the American prong-buck has a white patch behind and a black muzzle. The Tartarian antelope, the Ovis poli of High Asia, the Java wild ox, several species of deer, and a large number of antelopes have a similar conspicuous white patch behind, which, in contrast to the dusky body, must enable them to be seen and followed from a distance by their fellows. Where there are many species of nearly the same general size and form inhabiting the same region—as with the antelopes


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x Geographical Journal for April 1893. My best thanks are also due to Messrs. E. A. Maund, W. Franceys, and W. Ellerton Fry, for the numerous photographs of views taken by them in the interior of Africa, all of which were generously placed at my disposal from which to select suitable subjects for illustrations.

The manuscript of the book has been most carefully read over by Mr. John Coles, F.R.A.S., the Map Curator of the Royal Geographical Society, and travel-editor of the Field newspaper, who has always taken more than a friendly interest in my career as a hunter, naturalist, and explorer. At his suggestion I have adopted the spelling of native names recommended by the Royal Geographical Society.

Finally my thanks are due to my publishers, Messrs. Rowland Ward and Co., for the great pains they have taken to turn out the book in the best possible manner. The best artists procurable have been employed, and Mr. Rowland Ward has himself spent much time in personally supervising the many spirited drawings which cannot but add to any value the book may have. 2em


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 of Africa—we find many distinctive markings of a similar kind. The gazelles have variously striped and banded faces, besides white patches behind and on the flanks, as shown in the woodcut. The spring-bok has a white patch on the face and one on the sides, with a curiously distinctive white stripe above the tail, which is nearly concealed when the animal is at rest by a fold of skin but comes into full view when it is in motion, being thus quite analogous to the upturned white tail of the rabbit. In the pallah the white rump-mark is bordered with black, and the peculiar shape of the horns distinguishes it when seen from the front. The sable-antelope, the gems-bok, the oryx, the hart-beest, the bonte-bok, and the addax have each peculiar white markings; and they are besides characterised by horns so remarkably different in each species and so conspicuous, that it seems probable that the peculiarities in length, twist, and curvature have been differentiated for the purpose of recognition, rather than for any speciality of defence in species whose general habits are so similar.


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 It is interesting to note that these markings for recognition are very slightly developed in the antelopes of the woods and marshes. Thus, the grys-bok is nearly uniform in colour, except the long black-tipped ears; and it frequents the wooded mountains. The duyker-bok and the rhoode-bok are wary bush-haunters, and have no marks but the small white patch behind. The wood-haunting bosch-bok goes in pairs, and has hardly any distinctive marks on its dusky chestnut coat, but the male alone is horned. The large and handsome koodoo frequents brushwood, and its vertical white stripes are no doubt protective, while its magnificent spiral horns afford easy recognition. The eland, which is an inhabitant of the open country, is uniformly coloured, being sufficiently recognisable by its large size and distinctive form; but the Derbyan eland is a forest animal, and has a protectively striped coat. In like manner, the fine Speke's antelope, which lives entirely in the swamps and among reeds, has pale vertical stripes on the sides (protective), with white markings on face and breast for recognition. An inspection of the figures of antelopes and other animals in Wood's Natural History, or in other illustrated works, will give a better idea of the peculiarities of recognition markings than any amount of description.

Other examples of such coloration are to be seen in the dusky tints of the musk-sheep and the reindeer, to whom recognition at a distance on the snowy plains is of more importance than concealment from their few enemies. The conspicuous stripes and bands of the zebra and the quagga are probably due to the same cause, as may be the singular crests and face-marks of several of the monkeys and lemurs.


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 Among birds, these recognition marks are especially numerous and suggestive. Species which inhabit open districts are usually protectively coloured; but they generally possess some distinctive markings for the purpose of being easily recognised by their kind, both when at rest and during flight. Such are, the white bands or patches on the breast or belly of many birds, but more especially the head and neck markings in the form of white or black caps, collars, eye-marks or frontal patches, examples of which are seen in the three species of African plovers figured on page 221.

Recognition marks during flight are very important for all birds which congregate in flocks or which migrate together; and it is essential that, while being as conspicuous as possible, the marks shall not interfere with the general protective tints of the species when at rest. Hence they usually consist of well-contrasted markings on the wings and tail, which are concealed during repose but become fully visible when the bird takes flight. Such markings are well seen in our four British species of shrikes, each having quite different white marks on the expanded wings and on the tail feathers; and the same is the case with our three species of Saxicola—the stone-chat, whin-chat, and wheat-ear—which are thus easily recognisable on the wing, especially when seen from above, as they would be by stragglers looking out for their companions. The figures opposite, of the wings of two African species of stone-curlew which are sometimes found in the same districts, well illustrates these specific recognition marks. Though not very greatly different to our eyes, they are no doubt amply so to the sharp vision of the birds themselves.

Besides the white patches on the primaries here shown, the secondary feathers are, in some cases, so coloured as to afford very distinctive markings during flight, as seen in the central secondary quills of two African coursers (Fig. 21).

Most characteristic of all, however, are the varied markings of the outer tail-feathers, whose purpose is so well shown by their being almost always covered during repose by the two middle feathers, which are themselves quite unmarked and protectively tinted like the rest of the upper surface of the body. The figures of the expanded tails of two species of East Asiatic snipe, whose geographical ranges overlap each other,


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 will serve to illustrate this difference; which is frequently much greater and modified in an endless variety of ways (Fig. 22).

Numbers of species of pigeons, hawks, finches, warblers, ducks, and innumerable other birds possess this class of markings; and they correspond so exactly in general character with those of the mammalia, already described, that we cannot doubt they serve a similar purpose.

Those birds which are inhabitants of tropical forests, and which need recognition marks that shall be at all times visible among the dense foliage, and not solely or chiefly during flight, have usually small but brilliant patches of colour


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 on the head or neck, often not interfering with the generally protective character of their plumage. Such are the bright patches of blue, red, or yellow, by which the usually green Eastern barbets are distinguished; and similar bright patches of colour characterise the separate species of small green fruit-doves. To this necessity for specialisation in colour, by which each bird may easily recognise its kind, is probably due that marvellous variety in the peculiar beauties of some groups of birds. The Duke of Argyll, speaking of the humming birds, made the objection that "A crest of topaz is no better in the struggle for existence than a crest of sapphire. A frill ending in spangles of the emerald is no better in the battle of life than a frill ending in spangles of the ruby. A tail is not affected for the purposes of flight, whether its marginal or its central feathers are decorated with white;" and he goes on to urge that mere beauty and variety for their own sake are the only causes of these differences. But, on the principles here suggested, the divergence itself is useful, and must have been produced pari passu with the structural differences on which the differentiation of species depends; and thus we have explained the curious fact that prominent differences of colour often distinguish species otherwise very closely allied to each other.

Among insects, the principle of distinctive coloration for recognition has probably been at work in the production of the wonderful diversity of colour and marking we find everywhere, more especially among the butterflies and moths; and here its chief function may have been to secure the pairing together of individuals of the same species. In some of the moths this has been secured by a peculiar odour, which attracts the males to the females from a distance; but there is no evidence that this is universal or even general, and among butterflies, especially, the characteristic colour and marking, aided by size and form, afford the most probable means of recognition. That this is so is shown by the fact that "the common white butterfly often flies down to a bit of paper on the ground, no doubt mistaking it for one of its own species;" while, according to Mr. Collingwood, in the Malay Archipelago, "a dead butterfly pinned upon a conspicuous twig will often arrest an insect of the same species in its headlong flight, and


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 bring it down within easy reach of the net, especially if it be of the opposite sex." In a great number of insects, no doubt, form, motions, stridulating sounds, or peculiar odours, serve to distinguish allied species from each other, and this must be especially the case with nocturnal insects, or with those whose colours are nearly uniform and are determined by the need of protection; but by far the larger number of day-flying and active insects exhibit varieties of colour and marking, forming the most obvious distinction between allied species, and which have, therefore, in all probability been acquired in the process of differentiation for the purpose of checking the intercrossing of closely allied forms.

Whether this principle extends to any of the less highly organised animals is doubtful, though it may perhaps have affected the higher mollusca. But in marine animals it seems probable that the colours, however beautiful, varied, and brilliant they may often be, are in most cases protective, assimilating them to the various bright-coloured seaweeds, or to some other animals which it is advantageous for them to imitate.

Before proceeding to discuss some of the more recondite phenomena of animal coloration, it will be well to consider for a moment the extent of the ground we have already covered. Protective coloration, in some of its varied forms, has not improbably modified the appearance of one-half of the animals living on the globe. The white of arctic animals, the yellowish tints of the desert forms, the dusky hues of crepuscular and nocturnal species, the transparent or bluish tints of oceanic creatures, represent a vast host in themselves; but we have an equally numerous body whose tints are adapted to tropical foliage, to the bark of trees, or to the soil


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Page 1

Page 19

Collecting specimens of natural history—Meet Mr. and Mrs. Dorehill—Shoot leopard—Start for the Zambesi—Reach Manyanga's village—Timidity of the natives—Shoot sable antelope—Chikasi's village—My donkey is killed by hyænas—Cross the Mutiki river—Reach Se-fu-pi's—Mount Inyambari—Descend to the valley of the Zambesi—The Umsengaisi river—Impala antelopes—Reach the Zambesi—José Miguel Lobo—Start for Zumbo—Pass Perizengi's town—Black rhinoceros spoor—Sleep at Matakania's town—Cross the Panyami—A jovial host—Reach Kanyemba's—Arrival at Zumbo—Hospitality of the Portuguese—Collecting butterflies on the River Loangwa—Ruins of old Zumbo—Start for Mashunaland—Wild jasmine bushes—Cross the River


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 or dead leaves on or among which they habitually live. Then we have the innumerable special adaptations to the tints and forms of leaves, or twigs, or flowers; to bark or moss; to rock or pebble; by which such vast numbers of the insect tribes obtain protection; and we have seen that these various forms of coloration are equally prevalent in the waters of the seas and oceans, and are thus coextensive with the domain of life upon the earth. The comparatively small numbers which possess "terrifying" or "alluring" coloration may be classed under the general head of the protectively coloured.

But under the next head—colour for recognition—we have a totally distinct category, to some extent antagonistic or complementary to the last, since its essential principle is visibility rather than concealment. Yet it has been shown, I think, that this mode of coloration is almost equally important, since it not only aids in the preservation of existing species and in the perpetuation of pure races, but was, perhaps, in its earlier stages, a not unimportant factor in their development. To it we owe most of the variety and much of the beauty in the colours of animals; it has caused at once bilateral symmetry and general permanence of type; and its range of action has been perhaps equally extensive with that of coloration for concealment.

Certain relations between locality and coloration have long been noticed. Mr. Gould observed that birds from inland or continental localities were more brightly coloured than those living near the sea-coast or on islands, and he supposed that the more brilliant atmosphere of the inland stations was the explanation of the phenomenon. Many American naturalists have observed similar facts, and they assert that the intensity of the colours of birds and mammals increases from north to south, and also with the increase of humidity. This change is imputed by Mr. J.A. Allen to the direct action of the environment. He says: "In respect to the correlation of intensity of colour in animals with the degree of humidity, it would perhaps be more in accordance with cause and effect to express the law of correlation as a decrease of intensity of colour with


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 a decrease of humidity, the paleness evidently resulting from exposure and the blanching effect of intense sunlight, and a dry, often intensely heated atmosphere. With the decrease of the aqueous precipitation the forest growth and the protection afforded by arborescent vegetation gradually also decreases, as of course does also the protection afforded by clouds, the excessively humid regions being also regions of extreme cloudiness, while the dry regions are comparatively cloudless districts." Almost identical changes occur in birds, and are imputed by Mr. Allen to similar causes.

It will be seen that Mr. Gould and Mr. Allen impute opposite effects to the same cause, brilliancy or intensity of colour being due to a brilliant atmosphere according to the former, while paleness of colour is imputed by the latter to a too brilliant sun. According to the principles which have been established by the consideration of arctic, desert, and forest animals respectively, we shall be led to conclude that there has been no direct action in this case, but that the effects observed are due to the greater or less need of protection. The pale colour that is prevalent in arid districts is in harmony with the general tints of the surface; while the brighter tints or more intense coloration, both southward and in humid districts, are sufficiently explained by the greater shelter due to a more luxuriant vegetation and a shorter winter. The advocates of the theory that intensity of light directly affects the colours of organisms, are led into perpetual inconsistencies. At one time the brilliant colours of tropical birds and insects are imputed to the intensity of a tropical sun, while the same intensity of sunlight is now said to have a "bleaching" effect. The comparatively dull and sober hues of our northern fauna were once supposed to be the result of our cloudy skies; but now we are told that cloudy skies and a humid atmosphere intensify colour.

In my Tropical Nature (pp. 257-264) I have called attention to what is perhaps the most curious and decided relation of colour to locality which has yet been observed—the prevalence of white markings in the butterflies and birds of islands.


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 So many cases are adduced from so many different islands, both in the eastern and western hemisphere, that it is impossible to doubt the existence of some common cause; and it seems probable to me now, after a fuller consideration of the whole subject of colour, that here too we have one of the almost innumerable results of the principle of protective coloration. White is, as a rule, an uncommon colour in animals, but probably only because it is so conspicuous. Whenever it becomes protective, as in the case of arctic animals and aquatic birds, it appears freely enough; while we know that white varieties of many species occur occasionally in the wild state, and that, under domestication, white or parti-coloured breeds are freely produced. Now in all the islands in which exceptionally white-marked birds and butterflies have been observed, we find two features which would tend to render the conspicuous white markings less injurious—a luxuriant tropical vegetation, and a decided scarcity of rapacious mammals and birds. White colours, therefore, would not be eliminated by natural selection; but variations in this direction would bear their part in producing the recognition marks which are everywhere essential, and which, in these islands, need not be so small or so inconspicuous as elsewhere.

On a review of the whole subject, then, we must conclude that there is no evidence of the individual or prevalent colours of organisms being directly determined by the amount of light, or heat, or moisture, to which they are exposed; while, on the other hand, the two great principles of the need of concealment from enemies or from their prey, and of recognition by their own kind, are so wide-reaching in their application that they appear at first sight to cover almost the whole ground of animal coloration. But, although they are indeed wonderfully general and have as yet been very imperfectly studied, we are acquainted with other modes of coloration which have a different origin. These chiefly appertain to the very singular class of warning colours, from which arise the yet more extraordinary phenomena of mimicry; and they open up so curious a field of inquiry and present so many interesting problems, that a chapter must be devoted to them. Yet another chapter will


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 be required by the subject of sexual differentiation of colour and ornament, as to the origin and meaning of which I have arrived at different conclusions from Mr. Darwin. These various forms of coloration having been discussed and illustrated, we shall be in a position to attempt a brief sketch of the fundamental laws which have determined the general coloration of the animal world.


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 of his or her programme or of a general policy statement. Confidence shall be deemed to have been obtained when a single majority of the Members of Congress vote in favour.

Section 113

1. The Congress may require political responsibility from the Government by adopting a motion of censure by overall majority of its Members.

2. The motion of censure must be proposed by at least one tenth of the Members of Congress and shall include a candidate for the office of the Presidency of the Government.

3. The motion of censure may not be voted until five days after it has been submitted. During the first two days of this period, alternative motions may be submitted.

4. If the motion of censure is not adopted by the Congress, its signatories may not submit another during the same period of sessions.

Section 114

1. If the Congress withholds its confidence from the Government, the latter shall submit its resignation to the King, whereafter the President of the Government shall be nominated in accordance with the provisions of section 99.

2. If the Congress adopts a motion of censure, the Government shall submit its resignation to the King, and the candidate proposed in the motion of censure shall be deemed to have the confidence of the House for the purposes provided in section 99. The King shall appoint him or her President of the Government.

Section 115

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 the dissolution of the Congress, the Senate or the Cortes Generales, which shall be proclaimed by the King. The decree of dissolution shall set a date for the elections.

2. The proposal for dissolution may not be submitted while a motion of censure is pending.

3. There shall be no further dissolution until a year has elapsed since the previous one, except as provided for in section 99, subsection 5.

Section 116

1. An organic act shall make provision for the states of alarm, emergency and siege (martial law) and the powers and restrictions attached to each of them.

2. A state of alarm shall be proclaimed by the Government, by means of a decree agreed in Council of Ministers, for a maximum period of fifteen days. The Congress shall be informed and must meet immediately, and without its authorization the said period may not be extended. The decree shall specify the territory to which the effects of the proclamation apply.

3. A state of emergency shall be proclaimed by the Government by decree agreed in Council of Ministers, after prior authorization by the Congress. The authorization for and proclamation of a state of emergency must specifically state the effects thereof, the territory to which it is to apply and its duration, which may not exceed thirty days, subject to extension for a further thirty-day period, with the same requirements.

4. A state of siege (martial law) shall be proclaimed by overall majority of Congress solely on the Government's proposal. Congress shall determine its territorial extension, duration and terms. 53


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 5. The Congress may not be dissolved while any of the states referred to in the present section remains in force, and if the Houses are not in session, they shall be automatically convened. Their functioning, as well as that of the other constitutional State authorities, may not be interrupted while any of these states is in force.

If, in the event that the Congress has been dissolved or its term has expired, a situation giving rise to any of these states should occur, the powers of the Congress shall be assumed by its Permanent Deputation.

6. Proclamation of states of alarm, emergency and siege shall not affect the principle of liability of the Government or its agents as recognised in the Constitution and the laws.

Section 117

1. Justice emanates from the people and is administered on behalf of the King by judges and magistrates members of the Judicial Power who shall be independent, shall have fixity of tenure, shall be accountable for their acts and subject only to the rule of law.

2. Judges and magistrates may only be dismissed, suspended, transferred or retired on the grounds and subject to the safeguards provided for by the law.

3. The exercise of judicial authority in any kind of action, both in ruling and having judgments executed, is vested exclusively in the courts and tribunals laid down by the law, in accordance with the rules of jurisdiction and procedure which may be established therein. 54


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 4. Judges and courts shall not exercise any powers other than those indicated in the foregoing subsection and those which are expressly allocated to them by law as a guarantee of any right.

5. The principle of jurisdictional unity is the basis of the organization and operation of the courts. The law shall make provision for the exercise of military jurisdiction strictly within military framework and in cases of state of siege (martial law), in accordance with the principles of the Constitution.

6. Courts of exception are prohibited.

Section 118

It is compulsory to comply with sentences and other final resolutions of judges and courts, as well as to pay them such assistance as they may require in the course of trials and for the execution of judgments.

Section 119

Justice shall be free when thus provided for by law, and shall in any case be so in respect of those who have insufficient means to sue in court.

Section 120

1. Judicial proceedings shall be public, with the exceptions specified in the laws on procedure.

2. Proceedings shall be predominantly oral, especially in criminal cases.

3. Judgments shall always specify the grounds therefore, and they shall be delivered in a public hearing.

Section 121

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 compensation by the State, in accordance with the law.

Section 122

1. The Organic Act of the Judicial Power shall make provision for the setting up, operation and internal administration of courts and tribunals as well as for the legal status of professional judges and magistrates, who shall form a single body, and of the staff serving in the administration of justice.

2. The General Council of the Judicial Power is its governing body. An organic act shall lay down its status and the system of incompatibilities applicable to its members and their functions, especially in connection with appointments, promotions, inspection and the disciplinary system.

3. The General Council of the Judicial Power shall consist of the President of the Supreme Court, who shall preside it, and of twenty members appointed by the King for a five-year period, of which twelve shall be judges and magistrates of all judicial categories, under the terms provided for by the organic act; four nominated by the Congress and four by the Senate, elected in both cases by three-fifths of their members amongst lawyers and other jurists of acknowledged competence with more than fifteen years of professional practice.

Section 123

1. The Supreme Court, with jurisdiction over the whole of Spain, is the highest judicial body in all branches of justice, except with regard to provisions concerning constitutional guarantees.

2. The President of the Supreme Court shall be appointed by the King, on the General Council of the Judicial Powers' proposal in the manner to be laid down by the law.

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are personal qualifications universally considered to be of great importance to the female sex; yet is there something sad in the contemplation of the first of these, so great is the disproportion between the estimation in which it is regarded by young people in general, and its real value in the aggregate of human happiness. Indeed, when we think of its frailty, its superficial character, and the certainty of its final and utter extinction; and connect these considerations with the incalculable amount of ambition, envy, and false applause, which beauty has excited—we should rather be inclined to consider it a bane than a blessing to the human race.

Female beauty has ever been the theme of inspiration with poets, and with heroes, since the world began; and for all the sins and the follies, and they are many, for which beauty has formed the excuse, has not man been the abettor, if not the cause? Of his habitual and systematic treachery to his weak sister on this one point, what page—what book shall contain the record? Would that some pen more potent than ever yet was wielded by a human hand, would transcribe the dark history, and present it to his view; for happy, thrice happy will be that era, if it shall ever come, in the existence of woman, when man shall be true to her real interests, and when he shall esteem it his highest privilege to protect her—not from enchanted castles, from jealous rivals, or from personal foes, but from the more

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124 and fatal enemies which lurk within her own heart—from vanity, from envy, and from love of admiration.

To prove that I lay no unfounded charge at the door of man in this respect, let us look into society as it is. The beautiful woman! What court is paid to her! What extravagances are uttered and committed by those who compose her circle of admirers! She opens her lips;—men of high intellectual pretensions are proud to listen. Some trifling or vapid remark is all she utters. They applaud, if she attempts to be judicious; they laugh, if she aims at being gay; or they evince the most profound reverence for her sentiments, if the tone of her expression is grave. Listen to the flattery they offer at the shrine of this idol of an hour. No; it is too gross—too absurd for repetition. One thing, however, makes it serious. Such flattery is frequently at the expense of rivals, and even of friends; so that, while these admirers foster vanity, they are not satisfied without awaking the demon of envy in a soul—an immortal soul, which it ought to have been their generous and noble aim to shield from every taint of evil, and especially from so foul a taint as that of envy.

But let us turn to another scene in the drama of society. The very same men are disclaiming their unsuccessful efforts to obtain the favour of this beauty, and ridiculing the emptiness and the folly of the remarks they so lately applauded. Time passes on. The beauty so worshipped begins to wane. Other stars shine forth in the hemisphere, and younger belles assert superior claims to admiration. Who, then, remains of all that prostrate circle? Not one! They are all gone over to the junior claimant, and are laughing with her at the disappointment of the faded beauty.

This is a dark and melancholy picture, but for its truth I appeal to any who have mixed much in general society, who have either been beautiful themselves, or the confidants

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Rh of beauty, or who have been accustomed to hear the remarks of men on these subjects, when no beauty was present. I might appeal also to the fact, that personal beauty amongst women alone, receives no exaggerated or undue homage. Were there no men in the world, female beauty would be valued as a charm, but by no means as one of the highest order; and happily for women, an idea prevails amongst them, that those who want this charm, have the deficiency made up to them in talent, or in some other way.

Still, there is so natural and irresistible a delight in gazing upon beauty, that I never could understand the philosophy of those moralists who would endeavour to keep from a lovely girl, the knowledge that she was so. Her mirror is more faithful, and unless that be destroyed, the danger is, that she will suspect such moral managers of some sinister design in endeavouring to deceive her on this point, and that, in consequence, she will be put upon thinking still more of the value of a gift, with the possession of which she is not to be trusted. Far wiser is the part of that counsellor of youth, who, convinced that much of the danger attendant upon beauty, as a personal recommendation, arises out of low and ignorant views of the value of beauty itself, thus endeavours to show the folly of attaching importance to that which the touch of disease may at any hour destroy, and which time must inevitably efface.

The more the mind is expanded and enlightened, the more it is filled with a sense of what is admirable in the creation at large ; and the more it is impressed with the true image of moral beauty, the less it will be occupied with the consideration of any personal claim to flattery or applause. There will always be a circle of humble candidates for favour surrounding the unguarded steps of youth, whose influence will be excited on the side of personal beauty, perhaps more than in any other way. Without

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126 disrespect to the valuable class of servants, to which I allude, for I am convinced they know not what they do, I must express my fears, that they are often busily at work upon the young mind, long before the age of womanhood, instilling into it their own low views of beauty as a personal distinction; and it is against this influence, more especially as it begins the earliest, that I would call up all the power of moral and intellectual expansion, in order to fill the mind as early as possible with elevated thoughts of the creation in general, and of admiration for that part of it which is separate from self.

A being thus enlightened, will perceive that admiration is one of the higher faculties of our nature unknown to the brute creation, and one, the lawful exercise of which, affords us perhaps more enjoyment than any other. Upon the right employment of this faculty depends much of the moral tendency of human character. It is, therefore, of the utmost importance that we should learn in early life to admire only what is truly excellent; and as there is an excellence of beauty, which it is consonant with the higher attributes of our nature that we should admire, it necessarily follows, that to search for beauty as an essence pervading the universe, is an employment not unworthy of an intelligent and immortal being.

Let us then examine, so far as we are able to do so, "the treasures of earth, ocean, and air;" and we shall see that it has pleased the all-wise Creator, to diffuse the principle of beauty over every region of the world. The deep sea, into whose mysterious caves no human eye can penetrate is full of it. The blue ether, and the sailing clouds, sun, moon, and stars, are they not beautiful? and the fruitful garden of the earth, wherever nature smiles?

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Rh me. One can imagine how badly I wanted to be convinced.

She mixed me another highball, and a short one for herself. Over it she told me her name—Miss Dolby—and finally she left me with a last comforting assurance. But, nightmare or no, I did not sleep again that night. I sat in the parlor among the lamps, smoking and dipping into book after book. Countless times I felt my gaze drawn back to the painting over the fireplace, with the cross and the nail-pierced wretch and the shimmering pink dancers.

After the rising sun had filled the apartment with its honest light and cheer I felt considerably calmer. I slept all morning, and in the afternoon was disposed to agree with Miss Dolby that the whole business had been a bad dream, nothing more. Dressing, I went down the hall, knocked on her door and invited her to dinner with me.

It was a good dinner. Afterward we went to an amusing motion picture, with Charles Butterworth in it as I remember. After bidding her good-night, I went to my own place. Undressed and in bed, I lay awake. My late morning slumber made my eyes slow to close. Thus it was that I heard the faint shuffle of feet and, sitting up against my pillows, saw the glowing silhouettes of the Golgotha dancers. Alive and magnified, they were creeping into my bedroom.

I did not hesitate or shrink this time. I sprang up, tense and defiant.

"No, you don't!" I yelled at them. As they seemed to hesitate before the impact of my wild voice, I charged frantically. For a moment I scattered them and got through the bedroom door, as on the previous night. There was another shindy in the entry; this time they all got hold of me, like a pack of hounds, and wrestled me back against the wall. I writhe even now when I think of the unearthly hardness of their little gripping paws. Two on each arm were spread-eagling me upon the plaster. The cruciform position again!

I swore, yelled and kicked. One of them was in the way of my foot. He floated back, unhurt. That was their strength and horror—their ability to go flabby and non-resistant under smashing, flattening blows. Something tickled my palm, pricked it. The point of a spike....

"Miss Dolby!" I shrieked, as a child might call for its mother. "Help! Miss D——"

The door flew open; I must not have locked it. "Here I am," came her unafraid reply.

She was outlined against the rectangle of light from the hall. My assailants let go of me to dance toward her. She gasped but did not scream. I staggered along the wall, touched a light-switch, and the parlor just beyond us flared into visibility. Miss Dolby and I ran in to the lamp, rallying there as stone-age folk must have rallied at their fire to face the monsters of the night. I looked at her; she was still fully dressed, as I had left her, apparently had been sitting up. Her rouge made flat patches on her pale cheeks, but her eyes were level.

time the dancers did not retreat or vanish; they lurked in the comparative gloom of the entry, jigging and trembling as if mustering their powers and resolutions for another rush at us.

"You see," I chattered out to her, "it wasn't a nightmare."

She spoke, not in reply, but as if to herself. "They have no faces," she whispered. "No faces!" In the half-light that was diffused upon them from our lamp they presented the featurelessness of so many huge gingerbread boys, covered with pink icing. One of them, some kind


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488 of leader, pressed forward within the circle of the light. It daunted him a bit. He hesitated, but did not retreat.

From my center table Miss Dolby had picked up a bright paper-cutter. She poised it with the assurance of one who knows how to handle cutting instruments.

"When they come," she said steadily, "let's stand close together. We'll be harder to drag down that way."

I wanted to shout my admiration of her fearless front toward the dreadful beings, my thankfulness for her quick run to my rescue. All I could mumble was, "You're mighty brave."

She turned for a moment to look at the picture above my dying fire. My eyes followed hers. I think I expected to see a blank canvas—find that the painted dancers had vanished from it and had grown into the living ones. But they were still in the picture, and the cross and the victim were there, too. Miss Dolby read aloud the inscription:

"A living picture ... The artist knew what he was talking about, after all."

"Couldn't a living picture be killed?" I wondered.

It sounded uncertain, and a childish quibble to boot, but Miss Dolby exclaimed triumphantly, as at an inspiration.

"Killed? Yes!" she shouted. She sprang at the picture, darting out with the paper-cutter. The point ripped into one of the central figures in the dancing semicircle.

All the crowd in the entry seemed to give a concerted throb, as of startled protest. I swung, heart racing, to front them again. What had happened? Something had changed, I saw. The intrepid leader had vanished. No, he had not drawn back into the group. He had vanished.

Miss Dolby, too, had seen. She struck again, gashed the painted representation of another dancer. And this time the vanishing happened before my eyes, a creature at the rear of the group went out of existence as suddenly and completely as though a light had blinked out.

The others, driven by their danger, rushed.

I met them, feet planted. I tried to embrace them all at once, went over backward under them. I struck, wrenched, tore. I think I even bit something grisly and bloodless, like fungoid tissue, but I refuse to remember for certain. One or two of the forms struggled past me and grappled Miss Dolby. I struggled to my feet and pulled them back from her. There were not so many swarming after me now. I fought hard before they got me down again. And Miss Dolby kept tearing and stabbing at the canvas—again, again. Clutches melted from my throat, my arms. There were only two dancers left. I flung them back and rose. Only one left. Then none.

They were gone, gone into nowhere.

"That did it," said Miss Dolby breathlessly.

She had pulled the picture down. It was only a frame now, with ragged ribbons of canvas dangling from it.

I snatched it out of her hands and threw it upon the coals of the fire.

"Look," I urged her joyfully. "It's burning! That's the end. Do you see?"

"Yes, I see," she answered slowly. "Some fiend-ridden artist—his evil genius brought it to life."

"The inscription is the literal truth, then?" I supplied.

"Truth no more." She bent to watch the burning. "As the painted figures were destroyed, their incarnations faded."

We said nothing further, but sat down together and gazed as the flames ate the last thread of fabric, the last splinter of wood. Finally we looked up again and smiled at each other.

All at once I knew that I loved her.


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have now to deal with a class of colours which are the very opposite of those we have hitherto considered, since, instead of serving to conceal the animals that possess them or as recognition marks to their associates, they are developed for the express purpose of rendering the species conspicuous. The reason of this is that the animals in question are either the possessors of some deadly weapons, as stings or poison fangs, or they are uneatable, and are thus so disagreeable to the usual enemies of their kind that they are never attacked when their peculiar powers or properties are known. It is, therefore, important that they should not be mistaken for defenceless or eatable species of the same class or order, since in that case they might suffer injury, or even death, before their enemies discovered the danger or the uselessness of the attack. They require some signal or danger-flag which shall serve as a warning to would-be enemies not to attack them, and they have usually obtained this in the form of conspicuous or brilliant coloration, very distinct from the protective tints of the defenceless animals allied to them.


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While staying a few days, in July 1887, at the Summit Hotel on the Central Pacific Railway, I strolled out one evening after dinner, and on the road, not fifty yards from the house, I saw a pretty little white and black animal with a bushy tail coming towards me. As it came on at a slow pace and without any fear, although it evidently saw me, I thought at first that it must be some tame creature, when it suddenly occurred to me that it was a skunk. It came on till within five or six yards of me, then quietly climbed over a dwarf wall and disappeared under a small outhouse, in search of chickens, as the landlord afterwards told me. This animal possesses, as is well known, a most offensive secretion, which it has the power of ejecting over its enemies, and which effectually protects it from attack. The odour of this substance is so penetrating that it taints, and renders useless, everything it touches, or in its vicinity. Provisions near it become uneatable, and clothes saturated with it will retain the smell for several weeks, even though they are repeatedly washed and dried. A drop of the liquid in the eyes will cause blindness, and Indians are said not unfrequently to lose their sight from this cause. Owing to this remarkable power of offence the skunk is rarely attacked by other animals, and its black and white fur, and the bushy white tail carried erect when disturbed, form the danger-signals by which it is easily distinguished in the twilight or moonlight from unprotected animals. Its consciousness that it needs only to be seen to be avoided gives it that slowness of motion and fearlessness of aspect which are, as we shall see, characteristic of most creatures so protected.

It is among insects that warning colours are best developed, and most abundant. We all know how well marked and conspicuous are the colours and forms of the stinging wasps and bees, no one of which in any part of the world is known to be protectively coloured like the majority of defenceless insects. Most of the great tribe of Malacoderms among beetles are distasteful to insect-eating animals. Our red and


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 black Telephoridæ, commonly called "soldiers and sailors," were found, by Mr. Jenner Weir, to be refused by small birds. These and the allied Lampyridæ (the fireflies and glow-worms) in Nicaragua, were rejected by Mr. Belt's tame monkey and by his fowls, though most other insects were greedily eaten by them. The Coccinellidæ or lady-birds are another uneatable group, and their conspicuous and singularly spotted bodies serve to distinguish them at a glance from all other beetles.

These uneatable insects are probably more numerous than is supposed, although we already know immense numbers that are so protected. The most remarkable are the three families of butterflies—Heliconidæ, Danaidæ, and Acræidæ—comprising more than a thousand species, and characteristic respectively of the three great tropical regions—South America, Southern Asia, and Africa. All these butterflies have peculiarities which serve to distinguish them from every other group in their respective regions. They all have ample but rather weak wings, and fly slowly; they are always very abundant; and they all have conspicuous colours or markings, so distinct from those of other families that, in conjunction with their peculiar outline and mode of flight, they can usually be recognised at a glance. Other distinctive features are, that their colours are always nearly the same on the under surface of their wings as on the upper; they never try to conceal themselves, but rest on the upper surfaces of leaves or flowers; and, lastly, they all have juices which exhale a powerful scent, so that when one kills them by pinching the body, the liquid that exudes stains the fingers yellow, and leaves an odour that can only be removed by repeated washings.

Now, there is much direct evidence to show that this odour, though not very offensive to us, is so to most insect-eating creatures. Mr. Bates observed that, when set out to dry, specimens of Heliconidæ were less subject to the attacks of vermin; while both he and I noticed that they were not attacked by insect-eating birds or dragonflies, and that their wings were not found in the forest paths among the numerous wings of other butterflies whose bodies had been devoured. Mr. Belt once observed a pair of birds capturing insects for


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 their young; and although the Heliconidæ swarmed in the vicinity, and from their slow flight could have been easily caught, not one was ever pursued, although other butterflies did not escape. His tame monkey also, which would greedily munch up other butterflies, would never eat the Heliconidae. It would sometimes smell them, but always rolled them up in its hand and then dropped them.

We have also some corresponding evidence as to the distastefulness of the Eastern Danaidæ. The Hon. Mr. Justice Newton, who assiduously collected and took notes upon the Lepidoptera of Bombay, informed Mr. Butler of the British Museum that the large and swift-flying butterfly Charaxes psaphon, was continually persecuted by the bulbul, so that he rarely caught a specimen of this species which had not a piece snipped out of the hind wings. He offered one to a bulbul which he had in a cage, and it was greedily devoured, whilst it was only by repeated persecution that he succeeded in inducing the bird to touch a Danais.

Besides these three families of butterflies, there are certain groups of the great genus Papilio—the true swallow-tailed butterflies—which have all the characteristics of uneatable insects. They have a special coloration, usually red and black (at least in the females), they fly slowly, they are very abundant, and they possess a peculiar odour somewhat like that of the Heliconidæ. One of these groups is common in tropical America, another in tropical Asia, and it is curious that, although not very closely allied, they have each the same red and black colours, and are very distinct from all the other butterflies of their respective countries. There is reason to believe also that many of the brilliantly coloured and weak-flying diurnal moths, like the fine tropical Agaristidæ and burnet-moths, are similarly protected, and that their conspicuous colours serve as a warning of inedibility. The common burnet-moth (Anthrocera filipendula) and the equally conspicuous ragwort-moth (Euchelia jacobeae) have been proved to be distasteful to insect-eating creatures.


text:
Author:David Henry Keller

Novels

 * The Human Termites (1929)
 * Part 1 (September 1929)
 * Part 2 (October 1929)
 * Part 3 (November 1929)
 * The Conquerors (1929-30)
 * Part 1 (December 1929)
 * Part 2 (January 1930)
 * The Evening Star (1930)
 * Part 1 (April 1930)
 * Part 2 (May 1930)
 * The Time Projector (1931)
 * The Metal Doom (1932)
 * (part 1 of 3)
 * (part 2 of 3)
 * (part 3 of 3)
 * Life Everlasting (1934)
 * (renewed 4 Oct 1967)
 * (renewed 28 Oct 1976)
 * The Eternal Conflict (1949)
 * The Homunculus (1949)
 * The Lady Decides (1950)

Taine universe

 * Taine
 * The Feminine Metamorphosis (1929)
 * Euthanasia Limited (1929)
 * A Scientific Widowhood (1930)
 * Burning Water (1930)
 * Menacing Claws (1930)
 * The Cerebral Library (1931)
 * The Tree of Evil (1934)
 * Island of White Mice (1935)
 * Wolf Hollow Bubbles (1934)
 * Hands of Doom (1947)
 * Wolf Hollow Bubbles (1934)
 * Hands of Doom (1947)
 * Hands of Doom (1947)

 * The Menace

 * The Menace (1928)
 * The Gold Ship (1928)
 * The Tainted Flood (1928)
 * The Insane Avalanche (1928)

Wing Loo

 * The Ambidexter (1931)
 * The Cerebral Library (1931)
 * The Steam Shovel (1931)
 * The Steam Shovel (1931)
 * The Steam Shovel (1931)

Tales from Cornwall

 * The Oak Tree (1969)
 * The Sword and the Eagle (1969)
 * Raymond the Golden (1969)
 * The Thirty and One (1938) [also as by David H. Keller]
 * The Battle of the Toads (1929)
 * The Tailed Man of Cornwall (1929)
 * No Other Man (1929)
 * The Bride Well (1930)
 * Feminine Magic (1970)
 * (renewed 17 Jan 1968)
 * The Bride Well (1930)
 * Feminine Magic (1970)
 * (renewed 17 Jan 1968)
 * (renewed 17 Jan 1968)

Non-series fiction

 * Stenographer's Hands (1928)
 * The Thought Projector (1929)
 * The Threat of the Robot (1929)
 * (reprint)
 * White Collars (1929)
 * The Bloodless War (1929)
 * The Boneless Horror (1929)
 * The Flying Threat (1930)
 * The Moon Rays (1930)
 * Boomeranging 'Round the Moon (1930)
 * Service First (1931)
 * (renewed 28 May 1959)
 * The Sleeping War (1931)
 * Half-Mile Hill (1931)
 * (reprint)
 * (renewed 11 Feb 1960)
 * (renewed 11 Feb 1960)
 * (reprint)
 * A Piece of Linoleum (1933)
 * Life Everlasting (1934)
 * (part 1 of 2)
 * (part 2 of 2)
 * The Solitary Hunters
 * (part 1 of 3)
 * (part 2 of 3)
 * (part 3 of 3)
 * The Literary Corkscrew (1934)
 * The Dead Woman (1934)
 * Binding Deluxe (1934)
 * The Doorbell (1934)
 * Rider by Night (1934)
 * Men of Avalon (1935)
 * One-Way Tunnel (1935)
 * The Life Detour (1935)
 * The Living Machine (1935)
 * The Fireless Age (1937)
 * (part 1 of 2)
 * (part 2 of 2)
 * The Mother (1938)
 * (renewed 2 Dec 1968)
 * No More Friction (1939)
 * (renewed 22 Aug 1966)
 * (renewed 26 Dec 1967)
 * (renewed 2 Dec 1968)
 * Speed Will Be My Bride (1941)
 * The Red Death (1941)
 * The Pit of Doom (1942)
 * The Growing Wall (1942)
 * The Face in the Mirror (1947)
 * Heredity (1947)
 * The Perfumed Garden (1948)
 * The Door (1949)
 * The Final War (1949)
 * Chasm of Monsters (1951)
 * The Plot Machine (1951)
 * The Star (1952)
 * Fingers in the Sky (1952)
 * Sarah (1952)
 * The Folsom Flint (1952)
 * The God Wheel (1952)
 * The Opium Eater (1952)
 * The Question (1953)
 * The Golden Key (1953)
 * In Memoriam (1962)
 * Figment of a Dream (1962)
 * The Twins (1969)
 * The Landslide (1969)
 * The House Without Mirrors (1980)
 * The Purblind Prophet (1999) with Paul Spencer
 * The Beautiful Lady (2000)
 * Chapter 2 of Cosmos (1933)
 * (renewed 26 Dec 1967)
 * (renewed 2 Dec 1968)
 * Speed Will Be My Bride (1941)
 * The Red Death (1941)
 * The Pit of Doom (1942)
 * The Growing Wall (1942)
 * The Face in the Mirror (1947)
 * Heredity (1947)
 * The Perfumed Garden (1948)
 * The Door (1949)
 * The Final War (1949)
 * Chasm of Monsters (1951)
 * The Plot Machine (1951)
 * The Star (1952)
 * Fingers in the Sky (1952)
 * Sarah (1952)
 * The Folsom Flint (1952)
 * The God Wheel (1952)
 * The Opium Eater (1952)
 * The Question (1953)
 * The Golden Key (1953)
 * In Memoriam (1962)
 * Figment of a Dream (1962)
 * The Twins (1969)
 * The Landslide (1969)
 * The House Without Mirrors (1980)
 * The Purblind Prophet (1999) with Paul Spencer
 * The Beautiful Lady (2000)
 * Chapter 2 of Cosmos (1933)
 * The House Without Mirrors (1980)
 * The Purblind Prophet (1999) with Paul Spencer
 * The Beautiful Lady (2000)
 * Chapter 2 of Cosmos (1933)

Poetry

 * The Night The Red and Blue (1899)
 * Undo Everlasting (1902)
 * L'Envoi (1902)
 * A Melody (1902)
 * A Mother's Song (1902)
 * "Modern Science." in: Kotan September, 1948, Vol. 1, No. 1.

Non-Fiction

 * The Med-Lee: News Digest of the 9th Medical Battalion (1941)

title: Author:David Henry Keller


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 The most interesting and most conclusive example of warning coloration is, however, furnished by caterpillars, because in this case the facts have been carefully ascertained experimentally by competent observers. In the year 1866, when Mr. Darwin was collecting evidence as to the supposed effect of sexual selection in bringing about the brilliant coloration of the higher animals, he was struck by the fact that many caterpillars have brilliant and conspicuous colours, in the production of which sexual selection could have no place. We have numbers of such caterpillars in this country, and they are characterised not only by their gay colours but by not concealing themselves. Such are the mullein and the gooseberry caterpillars, the larvae of the Spurge hawk-moth|spurge hawk-moth, of the buff-tip, and many others. Some of these caterpillars are wonderfully conspicuous, as in the case of that noticed by Mr. Bates in South America, which was four inches long, banded across with black and yellow, and with bright red head, legs, and tail. Hence it caught the eye of any one who passed by, even at the distance of many yards.

Mr. Darwin asked me to try and suggest some explanation of this coloration; and, having been recently interested in the question of the warning coloration of butterflies, I suggested that this was probably a similar case,—that these conspicuous caterpillars were distasteful to birds and other insect-eating creatures, and that their bright non-protective colours and habit of exposing themselves to view, enabled their enemies to distinguish them at a glance from the edible kinds and thus learn not to touch them; for it must be remembered that the bodies of caterpillars while growing are so delicate, that a wound from a bird's beak would be perhaps as fatal as if they were devoured. At this time not a single experiment or observation had been made on the subject, but after I had brought the matter before the Entomological Society, two gentlemen, who kept birds and other tame animals, undertook to make experiments with a variety of caterpillars.

Mr. Jenner Weir was the first to experiment with ten species of small birds in his aviary, and he found that none of them would eat the following smooth-skinned conspicuous


text: Weird Tales/Volume 30/Issue 4/Tiger Cat

title: Weird Tales/Volume 30/Issue 4/Tiger Cat


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 —Abraxas grossulariata, Diloba cæaeruleocephala, Anthrocera filipendula, and Cucullia verbasci. He also found that they would not touch any hairy or spiny larvae, and he was satisfied that it was not the hairs or the spines, but the unpleasant taste that caused them to be rejected, because in one case a young smooth larva of a hairy species, and in another case the pupa of a spiny larva, were equally rejected. On the other hand, all green or brown caterpillars as well as those that resemble twigs were greedily devoured.

Mr. A.G. Butler also made experiments with some green lizards (Lacerta viridis), which greedily ate all kinds of food, including flies of many kinds, spiders, bees, butterflies, and green caterpillars; but they would not touch the caterpillar of the gooseberry-moth (Abraxas grossulariata), or the imago of the burnet-moth (Anthrocera filipendula). The same thing happened with frogs. When the gooseberry caterpillars were first given to them, "they sprang forward and licked them eagerly into their mouths; no sooner, however, had they done so, than they seemed to become aware of the mistake that they had made, and sat with gaping mouths, rolling their tongues about, until they had got quit of the nauseous morsels, which seemed perfectly uninjured, and walked off as briskly as ever." Spiders seemed equally to dislike them. This and another conspicuous caterpillar (Halia wavaria) were rejected by two species—the geometrical garden spider (Epeira diadema) and a hunting spider.

Some further experiments with lizards were made by Professor Weismann, quite confirming the previous observations; and in 1886 Mr. E.B. Poulton of Oxford undertook a considerable series of experiments, with many other species of larvæ and fresh kinds of lizards and frogs. Mr. Poulton then reviewed the whole subject, incorporating all recorded facts, as well as some additional observations made by Mr. Jenner Weir in 1886. More than a hundred species of larvæ or of perfect insects of various orders have now been made the subject of experiment, and the results completely confirm my original suggestion. In almost every case the protectively coloured larvæ have been greedily eaten by all kinds of insectivorous


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 animals, while, in the immense majority of cases, the conspicuous, hairy, or brightly coloured larvae have been rejected by some or all of them. In some instances the inedibility of the larvæ extends to the perfect insect, but not in others. In the former cases the perfect insect is usually adorned with conspicuous colours, as the burnet and ragwort moths; but in the case of the buff-tip, the moth resembles a broken piece of rotten stick, yet it is partly inedible, being refused by lizards. It is, however, very doubtful whether these are its chief enemies, and its protective form and colour may be needed against insectivorous birds or mammals.

Mr. Samuel H. Scudder, who has largely bred North American butterflies, has found so many of the eggs and larvæ destroyed by hymenopterous and dipterous parasites that he thinks at least nine-tenths, perhaps a greater proportion, never reach maturity. Yet he has never found any evidence that such parasites attack either the egg or the larva of the inedible Danais archippus, so that in this case the insect is distasteful to its most dangerous foes in all the stages of its existence, a fact which serves to explain its great abundance and its extension over almost the whole world.

One case has been found of a protectively coloured larva,—one, moreover, which in all its habits shows that it trusts to concealment to escape its enemies—which was yet always rejected by lizards after they had seized it, evidently under the impression that from its colour it would be eatable. This is the caterpillar of the very common moth Mania typica; and Mr. Poulton thinks that, in this case, the unpleasant taste is an incidental result of some physiological processes in the organism, and is itself a merely useless character. It is evident that the insect would not conceal itself so carefully as it does if it had not some enemies, and these are probably birds or small mammals, as its food-plants are said to be dock and willow-herb, not suggestive of places frequented by lizards; and it has been found by experiment that lizards and birds have not always the same likes and dislikes. The case is interesting, because it shows that nauseous fluids sometimes occur sporadically, and may thus be intensified by natural selection when required for the purpose


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 of protection. Another exceptional case is that of the very conspicuous caterpillar of the spurge hawk-moth (Deilephila euphorbiæ), which was at once eaten by a lizard, although, as it exposes itself on its food-plant in the daytime and is very abundant in some localities, it must almost certainly be disliked by birds or by some animals who would otherwise devour it. If disturbed while feeding it is said to turn round with fury and eject a quantity of green liquid, of an acid and disagreeable smell similar to that of the spurge milk, only worse.

These facts, and Mr. Poulton's evidence that some larvæ rejected by lizards at first will be eaten if the lizards are very hungry, show that there are differences in the amount of the distastefulness, and render it probable that if other food were wanting many of these conspicuous insects would be eaten. It is the abundance of the eatable kinds that gives value to the inedibility of the smaller number; and this is probably the reason why so many insects rely on protective colouring rather than on the acquisition of any kind of defensive weapons. In the long run the powers of attack and defence must balance each other. Hence we see that even the powerful stings of bees and wasps only protect them against some enemies, since a tribe of birds, the bee-eaters, have been developed which feed upon them, and some frogs and lizards do so occasionally.

The preceding outline will sufficiently explain the characteristics of "warning coloration" and the end it serves in nature. There are many other curious modifications of it, but these will be best appreciated after we have discussed the remarkable phenomenon of "mimicry," which is bound up with and altogether depends upon "warning colour," and is in some cases the chief indication we have of the possession of some offensive weapon to secure the safety of the species imitated.

This term has been given to a form of protective resemblance, in which one species so closely resembles another in external form and colouring as to be mistaken for it, although the two may not be really allied and often belong to distinct


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 families or orders. One creature seems disguised in order to be made like another; hence the terms "mimic" and mimicry, which imply no voluntary action on the part of the imitator. It has long been known that such resemblances do occur, as, for example, the clear-winged moths of the families Sesiidæ and Ægeriidæ, many of which resemble bees, wasps, ichneumons, or saw-flies, and have received names expressive of the resemblance; and the parasitic flies (Volucella) which closely resemble bees, on whose larvæ the larvæ of the flies feed.

The great bulk of such cases remained, however, unnoticed, and the subject was looked upon as one of the inexplicable curiosities of nature, till Mr. Bates studied the phenomenon among the butterflies of the Amazon, and, on his return home, gave the first rational explanation of it. The facts are, briefly, these. Everywhere in that fertile region for the entomologist the brilliantly coloured Heliconidæ abound, with all the characteristics which I have already referred to when describing them as illustrative of "warning coloration." But along with them other butterflies were occasionally captured, which, though often mistaken for them, on account of their close resemblance in form, colour, and mode of flight, were found on examination to belong to a very distinct family, the Pieridæ. Mr. Bates notices fifteen distinct species of Pieridæ, belonging to the genera Leptalis and Enterpe, each of which closely imitates some one species of Heliconidæ, inhabiting the same region and frequenting the same localities. It must be remembered that the two families are altogether distinct in structure. The larvae of the Heliconidæ are tubercled or spined, the pupae suspended head downwards, and the imago has imperfect forelegs in the male; while the larvæ of the Pieridæ are smooth, the pupæ are suspended with a brace to keep the head erect, and the forefeet are fully developed in both sexes. These differences are as large and as important as those between pigs and sheep, or between swallows and sparrows; while English entomologists will best understand the case by supposing that a species of Pieris in this country was coloured and shaped like a small tortoise-shell, while another species on the Continent was equally like a Camberwell beauty—so like in both


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 cases as to be mistaken when on the wing, and the difference only to be detected by close examination. As an example of the resemblance, woodcuts are given of one pair in which the colours are simple, being olive, yellow, and black, while the very distinct neuration of the wings and form of the head and body can be easily seen.

Besides these Pieridæ, Mr. Bates found four true Papilios, seven Erycinidæ, three Castnias (a genus of day-flying moths), and fourteen species of diurnal Bombycidæ, all imitating some species of Heliconidæ which inhabited the same district; and it is to be especially noted that none of these insects were so abundant as the Heliconidæ they resembled, generally they


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 were far less common, so that Mr. Bates estimated the proportion in some cases as not one to a thousand. Before giving an account of the numerous remarkable cases of mimicry in other parts of the world, and between various groups of insects and of higher animals, it will be well to explain briefly the use and purport of the phenomenon, and also the mode by which it has been brought about.

The fact has been now established that the Heliconidæ possess an offensive odour and taste, which lead to their being almost entirely free from attack by insectivorous creatures; they possess a peculiar form and mode of flight, and do not seek concealment; while their colours—although very varied, ranging from deep blue-black, with white, yellow, or vivid red bands and spots, to the most delicate semitransparent wings adorned with pale brown or yellow markings—are yet always very distinctive, and unlike those of all the other families of butterflies in the same country. It is, therefore, clear that if any other butterflies in the same region, which are eatable and suffer great persecution from insectivorous animals, should come to resemble any of these uneatable species so closely as to be mistaken for them by their enemies, they will obtain thereby immunity from persecution. This is the obvious and sufficient reason why the imitation is useful, and therefore why it occurs in nature. We have now to explain how it has probably been brought about, and also why a still larger number of persecuted groups have not availed themselves of this simple means of protection.

From the great abundance of the Heliconidæ all over tropical America, the vast number of their genera and species, and their marked distinctions from all other butterflies, it follows that they constitute a group of high antiquity, which in the course of ages has become more and more specialised, and owing to its peculiar advantages has now become a dominant and aggressive race. But when they first arose from some ancestral species or group which, owing to the food


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 of the larvæ or some other cause, possessed disagreeable juices that caused them to be disliked by the usual enemies of their kind, they were in all probability not very different either in form or coloration from many other butterflies. They would at that time be subject to repeated attacks by insect-eaters, and, even if finally rejected, would often receive a fatal injury. Hence arose the necessity for some distinguishing mark, by which the devourers of butterflies in general might learn that these particular butterflies were uneatable; and every variation leading to such distinction, whether by form, colour, or mode of flight, was preserved and accumulated by natural selection, till the ancestral Heliconoids became well distinguished from eatable butterflies, and thenceforth comparatively free from persecution. Then they had a good time of it. They acquired lazy habits, and flew about slowly. They increased abundantly and spread all over the country, their larvæ feeding on many plants and acquiring different habits; while the butterflies themselves varied greatly, and colour being useful rather than injurious to them, gradually diverged into the many coloured and beautifully varied forms we now behold.

But, during the early stages of this process, some of the Pieridæ, inhabiting the same district, happened to be sufficiently like some of the Heliconidæ to be occasionally mistaken for them. These, of course, survived while their companions were devoured. Those among their descendants that were still more like Heliconidæ again survived, and at length the imitation would become tolerably perfect. Thereafter, as the protected group diverged into distinct species of many different colours, the imitative group would occasionally be able to follow it with similar variations,—a process that is going on now, for Mr. Bates informs us that in each fresh district he visited he found closely allied representative species or varieties of Heliconidæ, and along with them species of Leptalis (Pieridæ), which had varied in the same way so as still to be exact imitations. But this process of imitation would be subject to check by the increasing acuteness of birds and other animals which, whenever the eatable Leptalis became numerous, would surely find them out, and would then probably attack both these and their friends the Heliconidæ in order to devour


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 the former and reject the latter. The Pieridæ would, however, usually be less numerous, because their larvæ are often protectively coloured and therefore edible, while the larvæ of the Heliconidæ are adorned with warning colours, spines, or tubercles, and are uneatable. It seems probable that the larvæ and pupæ of the Heliconidæ were the first to acquire the protective distastefulness, both because in this stage they are more defenceless and more liable to fatal injury, and also because we now find many instances in which the larvæ are distasteful while the perfect insects are eatable, but I believe none in which the reverse is the case. The larvæ of the Pieridæ are now beginning to acquire offensive juices, but have not yet obtained the corresponding conspicuous colours; while the perfect insects remain eatable, except perhaps in some Eastern groups, the under sides of whose wings are brilliantly coloured although this is the part which is exposed when at rest.

It is clear that if a large majority of the larvæ of Lepidoptera, as well as the perfect insects, acquired these distasteful properties, so as seriously to diminish the food supply of insectivorous and nestling birds, these latter would be forced by necessity to acquire corresponding tastes, and to eat with pleasure what some of them now eat only under pressure of hunger; and variation and natural selection would soon bring about this change.

Many writers have denied the possibility of such wonderful resemblances being produced by the accumulation of fortuitous variations, but if the reader will call to mind the large amount of variability that has been shown to exist in all organisms, the exceptional power of rapid increase possessed by insects, and the tremendous struggle for existence always going on, the difficulty will vanish, especially when we remember that nature has the same fundamental groundwork to act upon in the two groups, general similarity of forms, wings of similar texture and outline, and probably some original similarity of colour and marking. Yet there is evidently considerable difficulty in the process, or with these great resources at her command nature would have produced more of these mimicking forms than she has done. One reason of this deficiency probably is, that the imitators, being always fewer in number, have


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 not been able to keep pace with the variations of the much more numerous imitated form; another reason may be the ever-increasing acuteness of the enemies, which have again and again detected the imposture and exterminated the feeble race before it has had time to become further modified. The result of this growing acuteness of enemies has been, that those mimics that now survive exhibit, as Mr. Bates well remarks, "a palpably intentional likeness that is perfectly staggering," and also "that those features of the portrait are most attended to by nature which produce the most effective deception when the insects are seen in nature." No one, in fact, can understand the perfection of the imitation who has not seen these species in their native wilds. So complete is it in general effect that in almost every box of butterflies, brought from tropical America by amateurs, are to be found some species of the mimicking Pieridæ, Erycinidæ, or moths, and the mimicked Heliconidæ, placed together under the impression that they are the same species. Yet more extraordinary, it sometimes deceives the very insects themselves. Mr. Trimen states that the male Danais chrysippus is sometimes deceived by the female Diadema bolina which mimics that species. Dr. Fritz Müller, writing from Brazil to Professor Meldola, says, "One of the most interesting of our mimicking butterflies is Leptalis melite. The female alone of this species imitates one of our common white Pieridæ, which she copies so well that even her own male is often deceived; for I have repeatedly seen the male pursuing the mimicked species, till, after closely approaching and becoming aware of his error, he suddenly returned." This is evidently not a case of true mimicry, since the species imitated is not protected; but it may be that the less abundant Leptalis is able to mingle with the female Pieridæ and thus obtain partial immunity from attack. Mr. Kirby of the insect department of the British Museum informs me that there are several species of South American Pieridæ which the female Leptalis melite very nearly resembles. The case, however, is interesting as showing that the butterflies are themselves deceived by a resemblance which is not so great as that of some mimicking species.