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iv our existing dogs have descended. But this intermixture of distinct species will go a very little way in accounting for the peculiarities of the different breeds of dogs, many of which are totally unlike any wild animal. Such is the case with greyhounds, bloodhounds, bulldogs, Blenheim spaniels, terriers, pugs, turnspits, pointers, and many others; and these differ so greatly in size, shape, colour, and habits, as well as in the form and proportions of all the different parts of the body, that it seems impossible that they could have descended from any of the known wild dogs, wolves, or allied animals, none of which differ nearly so much in size, form, and proportions. We have here a remarkable proof that variation is not confined to superficial characters—to the colour, hair, or external appendages, when we see how the entire skeletons of such forms as the greyhound and the bulldog have been gradually changed in opposite directions till they are both completely unlike that of any known wild animal, recent or extinct. These changes have been the result of some thousands of years of domestication and selection, different breeds being used and preserved for different purposes; but some of the best breeds are known to have been improved and perfected in modern times. About the middle of the last century a new and improved kind of foxhound was produced; the greyhound was also greatly improved at the end of the last century, while the true bulldog was brought to perfection about the same period. The Newfoundland dog has been so much changed since it was first imported that it is now quite unlike any existing native dog in that island.

The most remarkable and instructive example of variation produced by human selection is afforded by the various races and breeds of domestic pigeons, not only because the variations produced are often most extraordinary in amount and diverse in character, but because in this case there is no doubt whatever that all have been derived from one wild species, the common rock-pigeon (Columba livia). As this is a very important point it is well to state the evidence on which the belief is founded. The wild rock-pigeon is of a slaty-blue


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90 colour, the tail has a dark band across the end, the wings have two black bands, and the outer tail-feathers are edged with white at the base. No other wild pigeon in the world has this combination of characters. Now in every one of the domestic varieties, even the most extreme, all the above marks, even to the white edging of the outer tail-feathers, are sometimes found perfectly developed. When birds belonging to two distinct breeds are crossed one or more times, neither of the parents being blue, or having any of the above-named marks, the mongrel offspring are very apt to acquire some of these characters. Mr. Darwin gives instances which he observed himself. He crossed some white fantails with some black barbs, and the mongrels were black, brown, or mottled. He also crossed a barb with a spot, which is a white bird with a red tail and red spot on the forehead, and the mongrel offspring were dusky and mottled. On now crossing these two sets of mongrels with each other, he obtained a bird of a beautiful blue colour, with the barred and white edged tail, and double-banded wings, so as almost exactly to resemble a wild rock-pigeon. This bird was descended in the second generation from a pure white and pure black bird, both of which when unmixed breed their kind remarkably true. These facts, well known to experienced pigeon-fanciers, together with the habits of the birds, which all like to nest in holes, or dovecots, not in trees like the great majority of wild pigeons, have led to the general belief in the single origin of all the different kinds.

In order to afford some idea of the great differences which exist among domesticated pigeons, it will be well to give a brief abstract of Mr. Darwin's account of them. He divides them into eleven distinct races, most of which have several sub-races.

Pouters.—These are especially distinguished by the enormously enlarged crop, which can be so inflated in some birds as almost to conceal the beak. They are very long in the body and legs and stand almost upright, so as to present a very distinct appearance. Their skeleton has become modified, the ribs being broader and the vertebræ more numerous than in other pigeons.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text: Dictionary of National Biography, 1885-1900/Moses, Henry


text: Dictionary of National Biography, 1885-1900/Moses, William Stainton


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iv  Carriers.—These are large, long-necked birds, with a long pointed beak, and the eyes surrounded with a naked carunculated skin or wattle, which is also largely developed at the base of the beak. The opening of the mouth is unusually wide. There are several sub-races, one being called Dragons.

Runts.—These are very large-bodied, long-beaked pigeons, with naked skin round the eyes. The wings are usually very long, the legs long, and the feet large, and the skin of the neck is often red. There are several sub-races, and these differ very much, forming a series of links between the wild rock-pigeon and the carrier.

Barbs.—These are remarkable for their very short and thick beak, so unlike that of most pigeons that fanciers compare it with that of a bullfinch. They have also a naked carunculated skin round the eyes, and the skin over the nostrils swollen.

Fantails.—Short-bodied and rather small-beaked pigeons, with an enormously developed tail, consisting usually of from fourteen to forty feathers instead of twelve, the regular number in all other pigeons, wild and tame. The tail spreads out like a fan and is usually carried erect, and the bird bends back its slender neck, so that in highly-bred varieties the head touches the tail. The feet are small, and they walk stiffly.

Turbits and Owls.—These are characterised by the feathers of the middle of neck and breast in front spreading out irregularly so as to form a frill. The Turbits also have a crest on the head, and both have the beak exceedingly short.

Tumblers.—These have a small body and short beak, but they are specially distinguished by the singular habit of tumbling over backwards during flight. One of the sub-races, the Indian Lotan or Ground tumbler, if slightly shaken and placed on the ground, will immediately begin tumbling head over heels until taken up and soothed. If not taken up, some of them will go on tumbling till they die.


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The Natural History of Ireland/Volume 1/The Spotted Eagle

THE SPOTTED EAGLE. The Rough-footed Eagle.

 * Aquila nosvia, Brisson.

 * Falco F. maculatus, Gmel.

Has been obtained in the south of Ireland.

In September, 1845, Mr. R. Davis, jun., of Clonmel, wrote to me respecting a bird then in Iris possession : " In contour, bill, eyes, legs, &c, it is a miniature of the golden eagle, but about one-third less than a male of that species ; except the tail-coverts and some spots on the wings and breast, it is entirely of a very deep glossy blackish- brown : the body is of small size, comparatively with the head, wings, and tail." [Claws, yellow ; beak, horn-colour, with a yellow streak at the base; weight, rather exceeding that of a full-grown raven. * ] This gentleman subsequently forwarded for my inspection, a coloured drawing of the bird, (which he believed to be of this species,) representing it in immature plumage. A wood-cut taken from the drawing has appeared in the second edition of Yarrell's British Birds, vol. i. p. 10, and in the Zoologist for January, 1846. In a communication made to the Annals of Natural History for Nov., 1845, p. 351, Mr. Davis stated that the bird was shot when preying on a rabbit, in January, 1845, on the estate of the Earl of Shannon, in the county of Cork. Another eagle of the same species, said to be similarly marked, but rather lighter in colour, had been killed there a few days before. The two birds had been observed for several weeks previously, sweeping over the low grounds between Castle-martyr and Clay Castle, near Youghal.

In a letter from Dr. Harvey of Cork, dated Oct. 30, 1845, it was remarked, with reference to the Irish specimen: — "Mr. Parker** took a portrait of the little eagle while I had it for a short time, and mentioned a singular coincidence. When on a visit to Mr. Butler of Waterville, a few days before the bird came under his inspection, that gentleman had mentioned a small brown eagle, in all respects like a golden eagle, except in being about half the size, as frequenting the mountains above Cahirciveen, in Kerry : — he had seen it occasionally during the last seven or eight years. To the Rev. Mr. Bastable, a clergyman of the neighbourhood, it was likewise known." I have little doubt, also, that a bird particularly described to myself, when visiting Horn Head (Donegal), in 1832, as having been shot there the previous year, was of this species.

The Spotted Eagle has not been met with in England or Scotland. In Continental Europe, it appears to inhabit chiefly the east and south ; but has been obtained in most of the countries southward of the Baltic Sea, including Belgium and France.

 * Noted by Mr. S. Moss, of Youghal, who received the bird iu a fresh state.
 * A gentleman whose splendid collection of coloured drawings of native birds,mostly life-size, and all executed by himself, attracted great admiration in the Natural History Section of the British Association at Cork, iu 1843.


text: Dictionary of National Biography, 1885-1900/North, John (1551?-1597)


text: Dictionary of National Biography, 1885-1900/Moss, Robert


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The Natural History of Ireland/Volume 1/The Rough-legged Buzzard

THE ROUGH-LEGGED BUZZAED.

 * Buteo lagopus, Brunn.
 * Falco Gmel.

Is only known as an extremely rare visitant.

About the middle of October, 1831, a bird of this species was taken near Dundonald, in the county of Down, by being knocked on the head with a stick, when gorged. The occurrence was noticed at the time in the Magazine of Natural History, vol. v. p. 578. On dissection, the remains of birds, and of a full-grown rat torn into four pieces, were found in its stomach. It was purchased Dr. J. D. Marshall, and is now in the Belfast Museum. This bird accords with Temminck's description of the adult male. It has not any indication of bands on either side of the tail : a band is represented near the tip on the under side, in Mr. Selbys figure of the female.

About this time, two others were seen at Killinchy, in the same county, and one of them was shot, but, through ignorance, it was lost as a specimen. In the autumn of 1836, the gamekeeper at Tollymore Park described a bird to me, which evidently had been of this species. It was shot a few year before (probably at the same period as the others) in Castlewellan demesne (Down), when carrying off a young rabbit.

In May, 1838, I was informed by Mr. Glennon, bird-preserver, Dublin, that a bird of this species (which he accurately described), was killed towards the end of the year 1837 (?) by the gamekeeper at Powerscourt, county of Wicklow.


text: Dictionary of National Biography, 1885-1900/Moss, Thomas


text: Dictionary of National Biography, 1885-1900/Mosse, Bartholomew


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92 Some English tumblers are almost equally persistent. A writer, quoted by Mr. Darwin, says that these birds generally begin to tumble almost as soon as they can fly; "at three months old they tumble well, but still fly strong; at five or six months they tumble excessively; and in the second year they mostly give up flying, on account of their tumbling so much and so close to the ground. Some fly round with the flock, throwing a clean summersault every few yards till they are obliged to settle from giddiness and exhaustion. These are called Air-tumblers, and they commonly throw from twenty to thirty summersaults in a minute, each clear and clean. I have one red cock that I have on two or three occasions timed by my watch, and counted forty summersaults in the minute. At first they throw a single summersault, then it is double, till it becomes a continuous roll, which puts an end to flying, for if they fly a few yards over they go, and roll till they reach the ground. Thus I had one kill herself, and another broke his leg. Many of them turn over only a few inches from the ground, and will tumble two or three times in flying across their loft. These are called House-tumblers from tumbling in the house. The act of tumbling seems to be one over which they have no control, an involuntary movement which they seem to try to prevent. I have seen a bird sometimes in his struggles fly a yard or two straight upwards, the impulse forcing him backwards while he struggles to go forwards."

The Short-faced tumblers are an improved sub-race which have almost lost the power of tumbling, but are valued for possessing some other characteristics in an extreme degree. They are very small, have almost globular heads, and a very minute beak, so that fanciers say the head of a perfect bird should resemble a cherry with a barleycorn stuck in it. Some of these weigh less than seven ounces, whereas the wild rock-pigeon weighs about fourteen ounces. The feet, too, are very short and small, and the middle toe has twelve or thirteen instead of fourteen or fifteen scutellæ. They have often only nine primary wing-feathers instead of ten as in all other pigeons.


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The Natural History of Ireland/Volume 1/The Honey Buzzard

THE HONEY BUZZARD.

 * Pernis apivorus, Linn, (sp.)
 * Falco

Is a very rare summer visitant.

On the 11th of June, 1833, a fine male specimen of the Honey Buzzard, unrecorded as having before occurred in Ireland, was shot by Robert G. Bomford, Esq., in his demesne of Annadale, near Belfast. This gentleman, on being informed of the rarity of the bird, kindly presented it to the Belfast Museum. A similar bird, most probably the female, accompanied the one that was shot. I saw the specimen when recent, and found the bill and forehead covered with cow-dung in such a manner, as to lead to the supposition that the bird had been searching for insects in that substance. On examination of the stomach, which was quite full, it was found to contain a few of the larva?, and some fragments of perfect coleopterous insects, several whitish-coloured hairy caterpillars, the pupae of a butterfly, and also of the the six-spot burnet-moth (Zygcena filipendulae), together with some pieces of grass, which it is presumed were taken with the last-named insect, it being on the stalks of grass that the pupae of this species of Zygaena are chiefly found. This insectivorous food must have been a matter of choice to the honey buzzard, the bird being in the full vigour of its powers, and the district in which it was killed abounding with such birds, as, were they its natural or wished-for prey, it might have easily captured and destroyed.

The individual thus dwelt upon, and of which a notice appeared in the Magazine of Natural History for 1833, vol. vi. p. 447, was a mature male. The bands on the tail exhibited a greater inequality than is represented in any figure I have seen, the first and second being less than an inch apart ; the third, more than two inches and a half distant from the second band.

In the summer of 1838, a honey buzzard, shot in the grounds about Kilruddery House, in the county of Wicklow, the seat of the Earl of Meath, came into the possession of T. W. Warren, Esq. of Dublin. A second individual was in company with it, and remained about the place for weeks after its supposed partner's death. This species has occasionally bred in England. On the 7th of June, 1839, an adult male was shot on the county of Antrim strand of Belfast bay, and purchased by Richard Langtry, Esq. The food in its stomach consisted of coleopterous insects only. A specimen of the honey buzzard was sent in a recent state from Gorey, county of Wexford, in the summer or autumn of 1841, to Mr. Glennon, bird-preserver, Dublin. *

observed and trapped in his demesne at Twizel, Northumberland.
 * Mr. Selby, in the Berwickshire Club Report for 1836, p. 109, gives a very interesting account of one of these birds, which was


text: Dictionary of National Biography, 1885-1900/Mosse, Miles


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iv Indian Frill-back.—In these birds the beak is very short, and the feathers of the whole body are reversed or turn backwards.

Jacobin.—These curious birds have a hood of feathers almost enclosing the head and meeting in front of the neck. The wings and tail are unusually long.

Trumpeter.—Distinguished by a tuft of feathers curling forwards over the beak, and the feet very much feathered. They obtain their name from the peculiar voice unlike that of any other pigeon. The coo is rapidly repeated, and is continued for several minutes. The feet are covered with feathers so large as often to appear like little wings.

comprises Laughers, Frill-backs, Nuns, Spots, and Swallows.—They are all very like the common rock-pigeon, but have each some slight peculiarity. The Laughers have a peculiar voice, supposed to resemble a laugh. The Nuns are white, with the head, tail, and primary wing-feathers black or red. The Spots are white, with the tail and a spot on the forehead red. The Swallows are slender, white in colour, with the head and wings of some darker colour.

Besides these races and sub-races a number of other kinds have been described, and about one hundred and fifty varieties can be distinguished. It is interesting to note that almost every part of the bird, whose variations can be noted and selected, has led to variations of a considerable extent, and many of these have necessitated changes in the plumage and in the skeleton quite as great as any that occur in the numerous distinct species of large genera. The form of the skull and beak varies enormously, so that the skulls of the Short-faced tumbler and some of the Carriers differ more than any wild pigeons, even those classed in distinct genera. The breadth and number of the ribs vary, as well as the processes on them; the number of the vertebræ and the length of the sternum also vary; and the perforations in the sternum vary in size and shape. The oil gland varies in development, and is sometimes absent. The number of the wing-feathers varies, and those of the tail to an enormous extent. The proportions of the leg and feet and the number


text: Dictionary of National Biography, 1885-1900/Mosses, Alexander


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94 of the scutellæ also vary. The eggs also vary somewhat in size and shape; and the amount of downy clothing on the young bird, when first hatched, differs very considerably. Finally, the attitude of the body, the manner of walking, the mode of flight, and the voice, all exhibit modifications of the most remarkable kind.

A very important kind of variation is that constitutional change termed acclimatisation, which enables any organism to become gradually adapted to a different climate from the parent stock. As closely allied species often inhabit different countries possessing very different climates, we should expect to find cases illustrating this change among our domesticated animals and cultivated plants. A few examples will therefore be adduced showing that such constitutional variation does occur.

Among animals the cases are not numerous, because no systematic attempt has been made to select varieties for this special quality. It has, however, been observed that, though no European dogs thrive well in India, the Newfoundland dog, originating from a severe climate, can hardly be kept alive. A better case, perhaps, is furnished by merino sheep, which, when imported directly from England, do not thrive, while those which have been bred in the intermediate climate of the Cape of Good Hope do much better. When geese were first introduced into Bogota, they laid few eggs at long intervals, and few of the young survived. By degrees, however, the fecundity improved, and in about twenty years became equal to what it is in Europe. According to Garcilaso, when fowls were first introduced into Peru they were not fertile, whereas now they are as much so as in Europe.

Plants furnish much more important evidence. Our nurserymen distinguish in their catalogues varieties of fruit-trees which are more or less hardy, and this is especially the case in America, where certain varieties only will stand the severe climate of Canada. There is one variety of pear, the Forelle, which both in England and France withstood frosts


text: Dictionary of National Biography, 1885-1900/Mossman, George


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Chronology of Mahatma Gandhi's life
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text: Dictionary of National Biography, 1885-1900/Mossman, Thomas Wimberley


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iv that killed the flowers and buds of all other kinds of pears. Wheat, which is grown over so large a portion of the world, has become adapted to special climates. Wheat imported from India and sown in good wheat soil in England produced the most meagre ears; while wheat taken from France to the West Indian Islands produced either wholly barren spikes or spikes furnished with two or three miserable seeds, while West Indian seed by its side yielded an enormous harvest. The orange was very tender when first introduced into Italy, and continued so as long as it was propagated by grafts, but when trees were raised from seed many of these were found to be hardier, and the orange is now perfectly acclimatised in Italy. Sweet-peas (Lathyrus odoratus) imported from England to the Calcutta Botanic Gardens produced few blossoms and no seed; those from France flowered a little better, but still produced no seed, but plants raised from seed brought from Darjeeling in the Himalayas, but originally derived from England, flower and seed profusely in Calcutta.

An observation by Mr. Darwin himself is perhaps even more instructive. He says: "On 24th May 1864 there was a severe frost in Kent, and two rows of scarlet runners (Phaseolus multiflorus) in my garden, containing 390 plants of the same age and equally exposed, were all blackened and killed except about a dozen plants. In an adjoining row of Fulmer's dwarf bean (Phaseolus vulgaris) one single plant escaped. A still more severe frost occurred four days afterwards, and of the dozen plants which had previously escaped only three survived; these were not taller or more vigorous than the other young plants, but they escaped completely, with not even the tips of their leaves browned. It was impossible to behold these three plants, with their blackened, withered, and dead brethren all around them, and not see at a glance that they differed widely in their constitutional power of resisting frost."

The preceding sketch of the variation that occurs among domestic animals and cultivated plants shows how wide it is in range and how great in amount; and we have good reason to believe that similar variation extends to all organised beings. In the class of fishes, for example, we have one kind which has


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96 been long domesticated in the East, the gold and silver carps; and these present great variation, not only of colour but in the form and structure of the fins and other external organs. In like manner, the only domesticated insects, hive bees and silkworm moths, present numbers of remarkable varieties which have been produced by the selection of chance variations just as in the case of plants and the higher animals.

It may be supposed, that the systematic selection which has been employed for the purpose of improving the races of animals or plants useful to man is of comparatively recent origin, though some of the different races are known to have been in existence in very early times. But Mr. Darwin has pointed out, that unconscious selection must have begun to produce an effect as soon as plants were cultivated or animals domesticated by man. It would have been very soon observed that animals and plants produced their like, that seed of early wheat produced early wheat, that the offspring of very swift dogs were also swift, and as every one would try to have a good rather than a bad sort this would necessarily lead to the slow but steady improvement of all useful plants and animals subject to man's care. Soon there would arise distinct breeds, owing to the varying uses to which the animals and plants were put. Dogs would be wanted chiefly to hunt one kind of game in one part of the country and another kind elsewhere; for one purpose scent would be more important, for another swiftness, for another strength and courage, for yet another watchfulness and intelligence, and this would soon lead to the formation of very distinct races. In the case of vegetables and fruits, different varieties would be found to succeed best in certain soils and climates; some might be preferred on account of the quantity of food they produced, others for their sweetness and tenderness, while others might be more useful on account of their ripening at a particular season, and thus again distinct varieties would be established. An instance of unconscious selection leading to distinct results in modern times is afforded by two flocks of Leicester sheep which both originated from the same stock, and were then bred pure for upwards of fifty years by two gentlemen, Mr. Buckley


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iv and Mr. Burgess. Mr. Youatt, one of the greatest authorities on breeding domestic animals, says: "There is not a suspicion existing in the mind of any one at all acquainted with the subject that the owner of either of them has deviated in any one instance from the pure blood of Mr. Bakewell's original flock, and yet the difference between the sheep possessed by these two gentlemen is so great that they have the appearance of being quite different varieties." In this case there was no desire to deviate from the original breed, and the difference must have arisen from some slight difference of taste or judgment in selecting, each year, the parents for the next year's stock, combined perhaps with some direct effect of the slight differences of climate and soil on the two farms.

Most of our domesticated animals and cultivated plants have come to us from the earliest seats of civilisation in Western Asia or Egypt, and have therefore been the subjects of human care and selection for some thousands of years, the result being that, in many cases, we do not know the wild stock from which they originally sprang. The horse, the camel, and the common bull and cow are nowhere found in a wild state, and they have all been domesticated from remote antiquity. The original of the domestic fowl is still wild in India and the Malay Islands, and it was domesticated in India and China before 1400 B.C. It was introduced into Europe about 600 B.C. Several distinct breeds were known to the Romans about the commencement of the Christian era, and they have since spread all over the civilised world and been subjected to a vast amount of conscious and unconscious selection, to many varieties of climate and to differences of food; the result being seen in the wonderful diversity of breeds which differ quite as remarkably as do the different races of pigeons already described.

In the vegetable kingdom, most of the cereals—wheat, barley, etc.—are unknown as truly wild plants; and the same is the case with many vegetables, for De Candolle states that out of 157 useful cultivated plants thirty-two are quite unknown in a wild state, and that forty more are of doubtful origin. It is not improbable that most of these do exist wild, but they have been so profoundly changed by thousands of years of cultivation as to be quite unrecognisable. The


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98 peach is unknown in a wild state, unless it is derived from the common almond, on which point there is much difference of opinion among botanists and horticulturists.

The immense antiquity of most of our cultivated plants sufficiently explains the apparent absence of such useful productions in Australia and the Cape of Good Hope, notwithstanding that they both possess an exceedingly rich and varied flora. These countries having been, until a comparatively recent period, inhabited only by uncivilised men, neither cultivation nor selection has been carried on for a sufficiently long time. In North America, however, where there was evidently a very ancient if low form of civilisation, as indicated by the remarkable mounds, earthworks, and other prehistoric remains, maize was cultivated, though it was probably derived from Peru; and the ancient civilisation of that country and of Mexico has given rise to no fewer than thirty-three useful cultivated plants.

In order that plants and animals may be improved and modified to any considerable extent, it is of course essential that suitable variations should occur with tolerable frequency. There seem to be three conditions which are especially favourable to the production of variations: (1) That the particular species or variety should be kept in very large numbers; (2) that it should be spread over a wide area and thus subjected to a considerable diversity of physical conditions; and (3) that it should be occasionally crossed with some distinct but closely allied race. The first of these conditions is perhaps the most important, the chance of variations of any particular kind being increased in proportion to the quantity of the original stock and of its annual offspring. It has been remarked that only those breeders who keep large flocks can effect much improvement; and it is for the same reason that pigeons and fowls, which can be so easily and rapidly increased, and which have been kept in such large numbers by so great a number of persons, have produced such strange and numerous varieties. In like manner, nurserymen who grow fruit and flowers in large quantities have a great advantage over private amateurs in the production of new varieties.


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The Natural History of Ireland/Volume 1/The Golden Eagle

THE GOLDEN EAGLE.

 * Aquila chrysaetos, Lin. (sp.) Footnote 1
 * fulva

Inhabits permanently several of the most lofty and retired mountain ranges throughout Ireland. [2012 note:Extinct in Ireland due to hunting since 1912, efforts are being made to re-introduce the species ]

Distribution, Eyries, Habits, &c.

The collection of my friend, William Sinclaire, Esq. of Belfast, contained a splendid specimen in adult plumage of the golden eagle, which was trapped some years ago on Muckish mountain, in the county of Donegal. In June, 1832, the gamekeeper of Mr. Stewart of " the Horn" Footnote 2. informed me when there, that since he entered on his present occupation in 1828, he had destroyed thirteen or fourteen eagles, of winch a single individual only was of this species : it was taken on one of the inland ountains of the Horn. When visiting about the same time the precipitous mountain of Rosheen, near Dunfanaghy, in that county, I was told that for a long time previous to the preceding twelve years, a pair of eagles had built their eyrie in one of the inaccessible cliffs.The situation selected for this eyrie indicates that the species was most probably the golden eagle." Footnote 3

 * [One of these birds, shot at the end of November, 1837, in the county of Londonderry, has come under my notice.]

In October, 1833, when looking over a collection of the British Falconida belonging to Wm. Sinclaire, Esq. with Mr. Adams, lately gamekeeper at Glenarm Park (county of Antrim), he at once recognised a golden eagle as the species of which he had killed four individuals in that locality. Only one sea eagle was obtained within the same period at Glenarm Park. On the 14th of Oct., 1835, I saw an adult specimen of the golden eagle, which was trapped the day before at Claggan (Antrim). It was accompanied by two others, but the attempt to capture them was unsuccessful.

By the late Dr. M'Donnell and another friend, both of whom well recollected the circumstance, I have been assured that the plan adopted by the Kerry peasant for supporting his family in a season of scarcity Footnote 4 was successfully resorted to about thirty years ago at Glenariff, in the county of Antrim. One of a pair of eaglets taken from a nest there was so placed, that its parents during the summer supplied it with rabbits and hares in such abundance, that its owner obtained, in addition to what the bird required, a sufficiency of animal food for himself and his family. The old birds did not alight with their prey, but circling for some time above the eaglet, apparently calculating the distance, they dropped the food within the limited reach of its chain.

A sporting friend, who was eye-witness to the fact, assures me that when out hunting among the Belfast mountains many years ago, an eagle, which from the darkness of its plumage he concluded was the golden, appeared above his hounds as they came to fault after a good chase, on the ascent to Devis, the highest of the range. As they came on the scent again, and were at full cry, the eagle for a short time kept above them, but at length advanced, and carried off the hare when at the distance of three or four hundred yards before the hounds.Footnote 5

In the autumn of 1836, the intelligent gamekeeper at Tollymore Park (Down), the seat of the Earl of Eoden, informed me that during the preceding nine years of his residence there, he had never met with the golden eagle among the neighbouring mountains of Mourne. In the summer of 1837, one of these birds was killed in that part of the country.

Mr. W. M'Calla of Roundstone, Connemara (Galway), made in substance the following communication to me in 1841. Golden eagles are not uncommon in that district Footnote 6 but seldom seek their prey in the neighbourhood of villages. Their eyries are generally among inaccessible cliffs in the range of mountains called the Twelve Pins ; but, in one instance, a pair bred in the level part of the country, selecting for the purpose a small island in the mountain lakes between Flin's house and Maam.

The Rev. B. J. Clarke remarked, when writing to me in March, 1841, from the wild district of Bermullet (county of Mayo), where he had resided for some time, that, although sea eagles are common there, he had seen the first golden eagle but a few days before : it was on the sand-banks within thirty yards of him. On visiting Achil, off the coast of Mayo, in June, 1834, (accompanied by Robert Ball, Esq. of Dublin,) Lieutenant Reynolds of the Preventive Service, a keen sportsman, and well acquainted with birds, assured, us that one or two pair of golden eagles breed annually in the island. When subsequently on the mountain of Croaghpatrick, which volcano-like terminates in a magnificent cone, and is in elevation the second in Connaught, we for a considerable time observed a pair of these eagles soaring above its summit. In the county of Kerry a few weeks afterwards, an eagle, supposed to be of this species, was seen from the top of Mangerton, which towers above the lakes of Killarney. Mr. Robert Patterson, of Belfast, when visiting this place in the previous autumn, made the following note: — "Near to the little lake called, the Devil's Punch- bowl, we disturbed, four eagles preying on a full- grown sheep; they rose majestically into the air as we approached. The people who were with us supposed that the sheep, being perhaps sickly, had been killed by the eagles, — a supposition corroborated by the quantity of fleece scattered over the ground for some yards in one direction. The flesh of the neck was completely removed, although that of every other part was untouched. We were assured, that two eagles will occasionally pursue a hare, one flying low and coursing it along the ground, the other keeping perpendicularly above the terrified animal, and occasionally changing their places, until the hare is completely wearied out. The same circumstance was mentioned a few days afterwards at Tralee, and again at Monasterevan : my informant in every instance stated the fact, not as a matter of hearsay, but as one which had fallen under his own knowledge." Footnote 7 The golden eagle has now become very scarce in Kerry. Footnote 8

A golden eagle was shot in Westmeath in Feb., 1838, when accompanied by another ; and a fine specimen was in the autumn of 1843 killed at Clontarf, near Dublin. Mr. Robert Davis, jun.,of Clonmel, notices a male bird in the plumage of the second year, as shot at Curraghmore, the seat of the Marquis of Waterford, early in June, 1837 ; and, at the end of the same month, an eyrie situated in the rocks above Counshenane Footnote 9 lake in the Comeragh mountains, county of Waterford, was robbed of an eaglet of this species. On the 21st of April, 1841, he sent persons to the same eyrie to procure eggs, who succeeded in obtaining two, which seemed to be about a fortnight laid, and were very dissimilar in size and appearance. He states that this bird is met with in Knockmeledown, and the Galtee mountains, and is occasionally seen far from its haunts. In the " Fauna of Cork," it is said to breed on the borders of that county, and in Tipperary.

I have never known the eyrie of the golden eagle to be in marine cliffs in Ireland. Mr. Macgillivray, who, in his History of British Birds, gives interesting particulars on this species from personal observation, states, on the authority of Mr. Forbes of South Ronaldshay, that it breeds on the headlands of Orkney (vol. 3, p. 230).

Docility, &c. — In the two excellent works, "Gardens and Menageries of the Zoological Society," and "Illustrations of British Ornithology," the golden eagle is characterized as indocile: in the latter work, Mr. Selby speaks from his own experience of two individuals which were kept by him for some years. But my friend Richard Langtry, Esq. of Fortwilliam, near Belfast, had in 1838 a bird of this species, which was extremely docile and tractable.Footnote 10 It was taken in the summer of that year from a nest in Inverness-shire Footnote 11 and came into his possession about the end of September. This bird at once became attached to its owner, and after being about a month in his possession, was given full liberty, — a high privilege to a golden eagle having the use of its wings, — but which was not abused, as it came to the lure whenever called. It evidently derived much pleasure from the application of the hand to its legs and plumage,, and permitted itself to be handled in any way. As one of the first steps towards training this eagle for the chace, it was hooded after the manner of a hunting hawk, but the practice wa soon abandoned as unnecessary, in consequence of its remaining quiet and contented when carried on the arm of its master. It was unwilling indeed to leave him even to take a flight, unless some special " quarry" was in view. When at liberty for the day, and my friend appeared in sight at any distance, his arm was no sooner held out towards the affectionate bird, than it came hurriedly flying to perch upon it. I have, when in his com-pany, — for it was quite indifferent to the presence of strangers, — seen it fly to him without any food being offered, not less than a dozen times within half an hour. When on the ground, and the lure was thrown comparatively near, this bird preferred running, — which it could do very fast, — to using its wings. It was also fed from the " fist." Live rats were several times turned out of the cage-trap to it; but before getting far away, they were invariably pounced upon. Pour full-grown rats have been taken at a meal; an entire heron, (Ardea cinerea), except the head and legs, was also eaten on one occasion. It differed somewhat in its man-ner of feeding from two sea eagles which were kept along with it; when the head and neck of a goose were offered, the golden eagle eat them wholly, the latter took the flesh off only, leaving the harder parts; and when entire birds were given, the sea eagle plucked many more feathers off than the golden; feathers off [Footnote 12 the latter assimilating to the peregrine falcon in this respect. This golden eagle was more partial to alighting on trees than the sea eagles were. Plying from one group of them to another, it in this manner followed its master about the demesne, indolently remaining as long as possible where it perched, consistently with always keeping him in sight. My friend discontinued any further training of this eagle on account of its boldness, as it flew not only at well-grown cygnets of the tame swan, but at the old birds themselves, which were obliged to take to the water for safety : it also flew at dogs, so that its liberty had to be lessened. This bird has now been for some years in the menagerie of the Royal Zoological Society, Phoenix Park, Dublin. A golden eagle, belonging to Mr. Wm. Sinclaire, was a more familiar bird than a sea eagle in his possession, but being kept in town, its docility was not much put to the proof.

Size and Weight. — The golden eagle is generally represented as larger than the sea eagle, but such specimens of the latter as I have examined, were invariably of superior size to the former, and I speak from comparison of adult individuals of the same sex. A similar remark is made in the "Fauna of Cork." Mr. Sinclaire's birds weight was 7 lbs. 14 oz. The specimen from Donegal in this gentleman's collection weighed on being captured 9 lbs : both of these birds were males. One of those killed in Glenarm Park (sex not noted) weighed 10 lbs. A large female sea eagle obtained in Donegal, and believed to be in her fourth or fifth year, weighed 14 lbs Footnote 13

Irides. — "When visiting in May, 1844, (along with my friend Wm. Ogilby, Esq.,) the magnificent menagerie at Knowsley in Lancashire, the seat of the Earl of Derby, the different coloured irides of two golden eagles attracted my attention ; one, a bird five years old, having them golden, while those of the other, whose age was not known, were of a whitish-brown hue. This is mentioned simply as a fact, and not as anything remarkable, as the irides of birds vary in colour at different ages. But I certainly did not expect so great diversity in the colour of the irides, as was exhibited in a pair of condors at the Surrey Zoological Gardens, in April, 1834 ; those of the male being of a dark dull yellow, while those of the female were of a brilliant red.

Great eagle-cage in the Zoological Gardens, Phoenix Park, Dublin.

More eagles of different species being brought together here than perhaps in any other place, Mr. E. Ball, the Honorary Secretary, Mr. J. V. Stewart, at my request, kindly supplied the following account of them in July, 1845.

"The great eagle-cage in the Garden of the Royal Zoological Society of Ireland is 36 feet long, 16 broad, and 16 high, and was erected at the expense of Sir Philip Crampton, Bart., as a place for the exercise of the large Carnivora, and consequently called a Deambulatorium. It failed in its original object. A tigress placed in it quailed, and seemed most anxious to regain her small den ; a lioness and a leopard had to be forced into it. Sometime afterwards I had seven Eagles placed in it as an experiment, and they seemed to agree perfectly. To these, additions have been made for the last four years, until the number now amounts to 17: viz., 3 Golden, 2 White-headed, and 12 Sea Eagles; for some time a Choka Eagle was of the number, but it has since been removed to a smaller cage. The eagles live together, if not in harmony, at least in a sort of mutual respect towards each other. I know of only one quarrel, and at this I happened to be present. A sea eagle pounced on a golden eagle ; the latter threw itself on its back, when the former with its talons seized it by the legs until it seemed to faint in agony, while the assailant gave forth its loudest barking cry in triumph. I had some difficulty in beating this bird off the other with a pole ; it was removed from the cage. On another occasion, a golden eagle was found in the bath, or large trough in which the eagles delight to roll ; it was supposed by the keeper to have been forced under water by one of the sea eagles, but more probably it got cramped, as the birds seem often to carry their bathing to excess. It is a remarkable fact, that a sea eagle but one year old, seemed to be generally acknowledged as the superior of the whole. This bird seized the first piece of food thrown into the cage as its acknowledged right ; but should any other eagle happen to get possession of it, the food was instantly given up on the approach of the young one, which, when full grown, was about the largest of the flock. The bathing of the eagles alluded to is remarkable. On observing that these birds, which in menageries are generally kept without water, exhibited a great desire to wash themselves, a large vessel was provided : when fresh water is put into this vessel, it is at once occupied by one of them, and surrounded by the others waiting their turn for a dip ; they constantly lie in it for some time until completely wetted."

generic) name, is that of the author quoted. Falco is the Linnean genus. "The black eagle fixes his talons between the deer's horns, and beats its wings constantly about its eyes, which puts the deer to run continually, till it falls into a ditch, or over a precipice, where it dies, and so becomes a prey to this cunning hunter. There are, at the same time, several other eagles of this kind, which flye on both sides of the deer, which frights it extremely, and contributes much to its more sudden destruction." work entitled " The Moor and the Loch ;" and in an article on " Highland Sports," in the Quarterly Review for Dec. 1845, being a review of Scrope's " fiays aDd Nights of Salmon Fishing," p. 103. s parrows have been taken in succession without a feather being plucked off.
 * Footnote 1 An abbreviation of the word species, implying that the specific (and not the
 * Footnote 2 The name given to the peninsula bounding the western entrance to Sheephaven, that terminates in the stupendous promontory of Horn Head
 * Footnote 3 Mr. R. Ball mentions a similar circumstance, in the following note. " In the summer of 1837, I saw a pair of golden eagles in the county of Kerry, that were proprietors of an eyrie in a cliff, from which they for a long time issued to commit predations on the poultry and lambs of the neighbouring peasantry, who in vain endeavoured to get at their nest."
 * Footnote 4 Smith's Kerry, p. 97-
 * Footnote 5 When grouse-shooting on the elevated and romantic mountains attached to Megarnie castle in Perthshire, late in October, 1829, my friend and I were surprised on one occasion by seeing a great number of grouse {Tetrao Scoticus) flying for a considerable distance so low as merely to overtop the heath. Passing us a short way off, they disappeared over an adjoining knoll. Thinking that they had alighted there, we hurried forward with our dogs, and not finding them, we on looking above perceived a golden eagle sailing along in the direction they had flown. This bird was presumed to have caused their unwonted flight, and its slow mode of progression gave us further hope that the grouse might still be near. Expecting them to lie well, in consequence of the eagle's being above, we carefully " beat " the ground for about a mile around, but not a grouse was found ; which, added to the eagle's flight being right onward, left little doubt that they had continued flying for a great distance in the unusual manner described.
 * Footnote 6 Flaherty, in his West or H-Iar Connanght, written in 1684, and published by the Irish Archaeological Society in 1846, remarks at p. 12: — "Here is a kind of black eagle, which kills the deere by grappling him with his claw, and forcing him to run headlong into precipices." The golden eagle being a bold bird, as well as darker coloured than the sea eagle, is, I presume, meant. The deer alluded to must be the stag, or red deer (Cervus elephas). The following note, from Martin's Western Islands, Isle of Lingay, p. 70, is appended by the editor to the quotation given: —
 * Footnote 7 This practice is mentioned in the "Wild sports of the West;" (Letter 19) in the
 * Footnote 8 Mr. R. Chute.
 * Footnote 9 Coumshingaun of Ordnance Survey Map.
 * Footnote 10 Mr. Yarrell (Brit. Birds, vol. i. p. 13,) after alluding to Mr. Selby's birds, remarks, that in the menageries of the Garden of the Zoological Society of London, where there are two golden and four white-tailed eagles, the keepers find the former the more tractable of the two species.
 * Footnote 11 At Aberarder, in this county, I saw a golden eagle displayed among the numerous "winged vermin" on the gable end of the shooting lodge, in September, 1842.
 * Footnote 12 Birds up to the size of sparrows are eaten whole by the golden eagle ; three
 * Footnote 13 Mr Stewart


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iv Although I believe, for reasons which will be given further on, that some amount of variability is a constant and necessary property of all organisms, yet there appears to be good evidence to show that changed conditions of life tend to increase it, both by a direct action on the organisation and by indirectly affecting the reproductive system. Hence the extension of civilisation, by favouring domestication under altered conditions, facilitates the process of modification. Yet this change does not seem to be an essential condition, for nowhere has the production of extreme varieties of plants and flowers been carried farther than in Japan, where careful selection continued for many generations must have been the chief factor. The effect of occasional crosses often results in a great amount of variation, but it also leads to instability of character, and is therefore very little employed in the production of fixed and well-marked races. For this purpose, in fact, it has to be carefully avoided, as it is only by isolation and pure breeding that any specially desired qualities can be increased by selection. It is for this reason that among savage peoples, whose animals run half wild, little improvement takes place; and the difficulty of isolation also explains why distinct and pure breeds of cats are so rarely met with. The wide distribution of useful animals and plants from a very remote epoch has, no doubt, been a powerful cause of modification, because the particular breed first introduced into each country has often been kept pure for many years, and has also been subjected to slight differences of conditions. It will also usually have been selected for a somewhat different purpose in each locality, and thus very distinct races would soon originate.

The important physiological effects of crossing breeds or strains, and the part this plays in the economy of nature, will be explained in a future chapter.

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100 been able to increase them to a marvellous extent by the simple process of always preserving the best varieties to breed from. Along with these larger variations others of smaller amount occasionally appear, sometimes in external, sometimes in internal characters, the very bones of the skeleton often changing slightly in form, size, or number; but as these secondary characters have been of no use to man, and have not been specially selected by him, they have, usually, not been developed to any great amount except when they have been closely dependent on those external characters which he has largely modified.

As man has considered only utility to himself, or the satisfaction of his love of beauty, of novelty, or merely of something strange or amusing, the variations he has thus produced have something of the character of monstrosities. Not only are they often of no use to the animals or plants themselves, but they are not unfrequently injurious to them. In the Tumbler pigeons, for instance, the habit of tumbling is sometimes so excessive as to injure or kill the bird; and many of our highly-bred animals have such delicate constitutions that they are very liable to disease, while their extreme peculiarities of form or structure would often render them quite unfit to live in a wild state. In plants, many of our double flowers, and some fruits, have lost the power of producing seed, and the race can thus be continued only by means of cuttings or grafts. This peculiar character of domestic productions distinguishes them broadly from wild species and varieties, which, as will be seen by and by, are necessarily adapted in every part of their organisation to the conditions under which they have to live. Their importance for our present inquiry depends on their demonstrating the occurrence of incessant slight variations in all parts of an organism, with the transmission to the offspring of the special characteristics of the parents; and also, that all such slight variations are capable of being accumulated by selection till they present very large and important divergencies from the ancestral stock.

We thus see, that the evidence as to variation afforded by animals and plants under domestication strikingly accords with that which we have proved to exist in a state of nature.


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iv And it is not at all surprising that it should be so, since all the species were in a state of nature when first domesticated or cultivated by man, and whatever variations occur must be due to purely natural causes. Moreover, on comparing the variations which occur in any one generation of domesticated animals with those which we know to occur in wild animals, we find no evidence of greater individual variation in the former than in the latter. The results of man's selection are more striking to us because we have always considered the varieties of each domestic animal to be essentially identical, while those which we observe in a wild state are held to be essentially diverse. The greyhound and the spaniel seem wonderful, as varieties of one animal produced by man's selection; while we think little of the diversities of the fox and the wolf, or the horse and the zebra, because we have been accustomed to look upon them as radically distinct animals, not as the results of nature's selection of the varieties of a common ancestor.


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the preceding chapters we have accumulated a body of facts and arguments which will enable us now to deal with the very core of our subject—the formation of species by means of natural selection. We have seen how tremendous is the struggle for existence always going on in nature owing to the great powers of increase of all organisms; we have ascertained the fact of variability extending to every part and organ, each of which varies simultaneously and for the most part independently; and we have seen that this variability is both large in its amount in proportion to the size of each part, and usually affects a considerable proportion of the individuals in the large and dominant species. And, lastly, we have seen how similar variations, occurring in cultivated plants and domestic animals, are capable of being perpetuated and accumulated by artificial selection, till they have resulted in all the wonderful varieties of our fruits, flowers, and vegetables, our domestic animals and household pets, many of which differ from each other far more in external characters, habits, and instincts than do species in


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CHAP. V a state of nature. We have now to inquire whether there is any analogous process in nature, by which wild animals and plants can be permanently modified and new races or new species produced.

Let us first consider what will be the effect of the struggle for existence upon the animals and plants which we see around us, under conditions which do not perceptibly vary from year to year or from century to century. We have seen that every species is exposed to numerous and varied dangers throughout its entire existence, and that it is only by means of the exact adaptation of its organisation—including its instincts and habits—to its surroundings that it is enabled to live till it produces offspring which may take its place when it ceases to exist. We have seen also that, of the whole annual increase only a very small fraction survives; and though the survival in individual cases may sometimes be due rather to accident than to any real superiority, yet we cannot doubt that, in the long run, those survive which are best fitted by their perfect organisation to escape the dangers that surround them. This "survival of the fittest" is what Darwin termed "natural selection," because it leads to the same results in nature as are produced by man's selection among domestic animals and cultivated plants. Its primary effect will, clearly, be to keep each species in the most perfect health and vigour, with every part of its organisation in full harmony with the conditions of its existence. It prevents any possible deterioration in the organic world, and produces that appearance of exuberant life and enjoyment, of health and beauty, that affords us so much pleasure, and which might lead a superficial observer to suppose that peace and quietude reigned throughout nature.

But the very same process which, so long as conditions remain substantially the same, secures the continuance of each species of animal or plant in its full perfection, will usually, under changed conditions, bring about whatever change of structure or habits may be necessitated by them. The changed conditions to which we refer are such as we know have occurred


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 throughout all geological time and in every part of the world. Land and water have been continually shifting their positions; some regions are undergoing subsidence with diminution of area, others elevation with extension of area; dry land has been converted into marshes, while marshes have been drained or have even been elevated into plateaux. Climate too has changed again and again, either through the elevation of mountains in high latitudes leading to the accumulation of snow and ice, or by a change in the direction of winds and ocean currents produced by the subsidence or elevation of lands which connected continents and divided oceans. Again, along with all these changes have come not less important changes in the distribution of species. Vegetation has been greatly modified by changes of climate and of altitude; while every union of lands before separated has led to extensive migrations of animals into new countries, disturbing the balance that before existed among its forms of life, leading to the extermination of some species and the increase of others.

When such physical changes as these have taken place, it is evident that many species must either become modified or cease to exist. When the vegetation has changed in character the herbivorous animals must become able to live on new and perhaps less nutritious food; while the change from a damp to a dry climate may necessitate migration at certain periods to escape destruction by drought. This will expose the species to new dangers, and require special modifications of structure to meet them. Greater swiftness, increased cunning, nocturnal habits, change of colour, or the power of climbing trees and living for a time on their foliage or fruit, may be the means adopted by different species to bring themselves into harmony with the new conditions; and by the continued survival of those individuals, only, which varied sufficiently in the right direction, the necessary modifications of structure or of function would be brought about, just as surely as man has been able to breed the greyhound to hunt by sight and the foxhound by scent, or has produced from the same wild plant such distinct forms as the cauliflower and the brussels sprouts.

We will now consider the special characteristics of the changes in species that are likely to be effected, and how far they agree with what we observe in nature.


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V

In species which have a wide range the struggle for existence will often cause some individuals or groups of individuals to adopt new habits in order to seize upon vacant places in nature where the struggle is less severe. Some, living among extensive marshes, may adopt a more aquatic mode of life; others, living where forests abound, may become more arboreal. In either case we cannot doubt that the changes of structure needed to adapt them to their new habits would soon be brought about, because we know that variations in all the external organs and all their separate parts are very abundant and are also considerable in amount. That such divergence of character has actually occurred we have some direct evidence. Mr. Darwin informs us that in the Catskill Mountains in the United States there are two varieties of wolves, one with a light greyhound-like form which pursues deer, the other more bulky with shorter legs, which more frequently attacks sheep. Another good example is that of the insects in the island of Madeira, many of which have either lost their wings or have had them so much reduced as to be useless for flight, while the very same species on the continent of Europe possess fully developed wings. In other cases the wingless Madeira species are distinct from, but closely allied to, winged species of Europe. The explanation of this change is, that Madeira, like many oceanic islands in the temperate zone, is much exposed to sudden gales of wind, and as most of the fertile land is on the coast, insects which flew much would be very liable to be blown out to sea and lost. Year after year, therefore, those individuals which had shorter wings, or which used them least, were preserved; and thus, in time, terrestrial, wingless, or imperfectly winged races or species have been produced. That this is the true explanation of this singular fact is proved by much corroborative evidence. There are some few flower-frequenting insects in Madeira to whom wings are essential, and in these the wings are somewhat larger than in the same species on the mainland. We thus see that there is no general tendency to the abortion of wings in Madeira, but that it is simply a case of adaptation to new conditions. Those insects


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 to whom wings were not absolutely essential escaped a serious danger by not using them, and the wings therefore became reduced or were completely lost. But when they were essential they were enlarged and strengthened, so that the insect could battle against the winds and save itself from destruction at sea. Many flying insects, not varying fast enough, would be destroyed before they could establish themselves, and thus we may explain the total absence from Madeira of several whole families of winged insects which must have had many opportunities of reaching the islands. Such are the large groups of the tiger-beetles (Cicindelidæ), the chafers (Melolonthidæ), the click-beetles (Elateridæ), and many others.

But the most curious and striking confirmation of this portion of Mr. Darwin's theory is afforded by the case of Kerguelen Island. This island was visited by the Transit of Venus expedition. It is one of the stormiest places on the globe, being subject to almost perpetual gales, while, there being no wood, it is almost entirely without shelter. The Rev. A. E. Eaton, an experienced entomologist, was naturalist to the expedition, and he assiduously collected the few insects that were to be found. All were incapable of flight, and most of them entirely without wings. They included a moth, several flies, and numerous beetles. As these insects could hardly have reached the islands in a wingless state, even if there were any other known land inhabited by them—which there is not—we must assume that, like the Madeiran insects, they were originally winged, and lost their power of flight because its possession was injurious to them.

It is no doubt due to the same cause that some butterflies on small and exposed islands have their wings reduced in size, as is strikingly the case with the small tortoise-shell butterfly (Vanessa urtica) inhabiting the Isle of Man, which is only about half the size of the same species in England or Ireland; and Mr. Wollaston notes that Vanessa callirhoe—a closely allied South European form of our red-admiral butterfly—is permanently smaller in the small and bare island of Porto Santo than in the larger and more wooded adjacent island of Madeira.

A very good example of comparatively recent divergence of character, in accordance with new conditions of life, is afforded by our red grouse. This bird, the Lagopus scoticus of


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V naturalists, is entirely confined to the British Isles. It is, however, very closely allied to the willow grouse (Lagopus albus), a bird which ranges all over Europe, Northern Asia, and North America, but which, unlike our species, changes to white in winter. No difference in form or structure can be detected between the two birds, but as they differ so decidedly in colour—our species being usually rather darker in winter than in summer, while there are also slight differences in the call-note and in habits,—the two species are generally considered to be distinct. The differences, however, are so clearly adaptations to changed conditions that we can hardly doubt that, during the early part of the glacial period, when our islands were united to the continent, our grouse was identical with that of the rest of Europe. But when the cold passed away and our islands became permanently separated from the mainland, with a mild and equable climate and very little snow in winter, the change to white at that season became hurtful, rendering the birds more conspicuous instead of serving as a means of concealment. The colour was, therefore, gradually changed by the process of variation and natural selection; and as the birds obtained ample shelter among the heather which clothes so many of our moorlands, it became useful for them to assimilate with its brown and dusky stems and withered flowers rather than with the snow of the higher mountains. An interesting confirmation of this change having really occurred is afforded by the occasional occurrence in Scotland of birds with a considerable amount of white in the winter plumage. This is considered to be a case of reversion to the ancestral type, just as the slaty colours and banded wings of the wild rock-pigeon sometimes reappear in our fancy breeds of domestic pigeons.

The principle of "divergence of character" pervades all nature from the lowest groups to the highest, as may be well seen in the class of birds. Among our native species we see it well marked in the different species of titmice, pipits, and chats. The great titmouse (Parus major) by its larger size and stronger bill is adapted to feed on larger insects, and is even said sometimes to kill small and weak birds. The smaller and weaker coal titmouse (Parus ater) has adopted a


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 more vegetarian diet, eating seeds as well as insects, and feeding on the ground as well as among trees. The delicate little blue titmouse (Parus cœruleus), with its very small bill, feeds on the minutest insects and grubs which it extracts from crevices of bark and from the buds of fruit-trees. The marsh titmouse, again (Parus palustris), has received its name from the low and marshy localities it frequents; while the crested titmouse (Parus cristatus) is a northern bird frequenting especially pine forests, on the seeds of which trees it partially feeds. Then, again, our three common pipits—the tree-pipit (Anthus arboreus), the meadow-pipit (Anthus pratensis), and the rock-pipit or sea-lark (Anthus obscurus) have each occupied a distinct place in nature to which they have become specially adapted, as indicated by the different form and size of the hind toe and claw in each species. So, the stone-chat (Saxicola rubicola), the whin-chat (S. rubetra), and the wheat-ear (S. œnanthe) are more or less divergent forms of one type, with modifications in the shape of the wing, feet, and bill adapting them to slightly different modes of life. The whin-chat is the smallest, and frequents furzy commons, fields, and lowlands, feeding on worms, insects, small molluscs, and berries; the stone-chat is next in size, and is especially active and lively, frequenting heaths and uplands, and is a permanent resident with us, the two other species being migrants; while the larger and more conspicuous wheat-ear, besides feeding on grubs, beetles, etc., is able to capture flying insects on the wing, something after the manner of true flycatchers.

These examples sufficiently indicate how divergence of character has acted, and has led to the adaptation of numerous allied species, each to a more or less special mode of life, with the variety of food, of habits, and of enemies which must necessarily accompany such diversity. And when we extend our inquiries to higher groups we find the same indications of divergence and special adaptation, often to a still more marked extent. Thus we have the larger falcons, which prey upon birds, while some of the smaller species, like the hobby (Falco subbuteo), live largely on insects. The true falcons capture their prey in the air, while the hawks usually seize it on or near the ground, feeding on hares, rabbits, squirrels, grouse, pigeons, and poultry. Kites and buzzards, on the


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V other hand, seize their prey upon the ground, and the former feed largely on reptiles and offal as well as on birds and quadrupeds. Others have adopted fish as their chief food, and the osprey snatches its prey from the water with as much facility as a gull or a petrel; while the South American caracaras (Polyborus) have adopted the habits of vultures and live altogether on carrion. In every great group there is the same divergence of habits. There are ground-pigeons, rock-pigeons, and wood-pigeons,—seed-eating pigeons and fruit-eating pigeons; there are carrion-eating, insect-eating, and fruit-eating crows. Even kingfishers are, some aquatic, some terrestrial in their habits; some live on fish, some on insects, some on reptiles. Lastly, among the primary divisions of birds we find a purely terrestrial group—the Ratitæ, including the ostriches, cassowaries, etc.; other great groups, including the ducks, cormorants, gulls, penguins, etc., are aquatic; while the bulk of the Passerine birds are aerial and arboreal. The same general facts can be detected in all other classes of animals. In the mammalia, for example, we have in the common rat a fish-eater and flesh-eater as well as a grain-eater, which has no doubt helped to give it the power of spreading over the world and driving away the native rats of other countries. Throughout the Rodent tribe we find everywhere aquatic, terrestrial, and arboreal forms. In the weasel and cat tribes some live more in trees, others on the ground; squirrels have diverged into terrestrial, arboreal, and flying species; and finally, in the bats we have a truly aerial, and in the whales a truly aquatic order of mammals. We thus see that, beginning with different varieties of the same species, we have allied species, genera, families, and orders, with similarly divergent habits, and adaptations to different modes of life, indicating some general principle in nature which has been operative in the development of the organic world. But in order to be thus operative it must be a generally useful principle, and Mr. Darwin has very clearly shown us in what this utility consists.

Divergence of character has a double purpose and use. In the first place it enables a species which is being overcome


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 by rivals, or is in process of extinction by enemies, to save itself by adopting new habits or by occupying vacant places in nature. This is the immediate and obvious effect of all the numerous examples of divergence of character which we have pointed out. But there is another and less obvious result, which is, that the greater the diversity in the organisms inhabiting a country or district the greater will be the total amount of life that can be supported there. Hence the continued action of the struggle for existence will tend to bring about more and more diversity in each area, which may be shown to be the case by several kinds of evidence. As an example, a piece of turf, three feet by four in size, was found by Mr. Darwin to contain twenty species of plants, and these twenty species belonged to eighteen genera and to eight orders, showing how greatly they differed from each other. Farmers find that a greater quantity of hay is obtained from ground sown with a variety of genera of grasses, clover, etc., than from similar land sown with one or two species only; and the same principle applies to rotation of crops, plants differing very widely from each other giving the best results. So, in small and uniform islands, and in small ponds of fresh water, the plants and insects, though few in number, are found to be wonderfully varied in character.

The same principle is seen in the naturalisation of plants and animals by man's agency in distant lands, for the species that thrive best and establish themselves permanently are not only very varied among themselves but differ greatly from the native inhabitants. Thus, in the Northern United States there are, according to Dr. Asa Gray, 260 naturalised flowering plants which belong to no less than 162 genera; and of these, 100 genera are not natives of the United States. So, in Australia, the rabbit, though totally unlike any native animal, has increased so much that it probably outnumbers in individuals all the native mammals of the country; and in New Zealand the rabbit and the pig have equally multiplied. Darwin remarks that this "advantage of diversification of structure in the inhabitants of the same region is, in fact, the same as that of the physiological division of labour in the organs of the same body. No physiologist doubts that a


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V stomach adapted to digest vegetable matter alone, or flesh alone, draws more nutriment from these substances. So, in the general economy of any land, the more widely and perfectly the animals and plants are diversified for different habits of life, so will a greater number of individuals be capable of there supporting themselves."

One of the curious results of the general action of this principle in nature is, that the most closely allied species—those whose differences though often real and important are hardly perceptible to any one but a naturalist—are usually not found in the same but in widely separated countries. Thus, the nearest allies to our European golden plover are found in North America and East Asia; the nearest ally of our European jay is found in Japan, although there are several other species of jays in Western Asia and North Africa; and though we have several species of titmice in England they are not very closely allied to each other. The form most akin to our blue tit is the azure tit of Central Asia (Parus azureus); the Parus ledouci of Algeria is very near our coal tit, and the Parus lugubris of South-Eastern Europe and Asia Minor is nearest to our marsh tit. So, our four species of wild pigeons—the ring-dove, stock-dove, rock-pigeon, and turtle-dove—are not closely allied to each other, but each of them belongs, according to some ornithologists, to a separate genus or subgenus, and has its nearest relatives in distant parts of Asia and Africa. In mammalia the same thing occurs. Each mountain region of Europe and Asia has usually its own species of wild sheep and goat, and sometimes of antelope and deer; so that in each region there is found the greatest diversity in this class of animals, while the closest allies inhabit quite distinct and often distant areas. In plants we find the same phenomenon prevalent. Distinct species of columbine are found in Central Europe (Aguilegia vulgaris), in Eastern Europe, and Siberia (A. glandulosa), in the Alps (A. Alpina), in the Pyrenees (A. pyrenaiea), in the Greek mountains (A. ottonis), and in Corsica (A. Bernardi), but rarely are two


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 species found in the same area. So, each part of the world has its own peculiar forms of pines, firs, and cedars, but the closely allied species or varieties are in almost every case inhabitants of distinct areas. Examples are the deodar of the Himalayas, the cedar of Lebanon, and that of North Africa, all very closely allied but confined to distinct areas; and the numerous closely allied species of true pine (genus Pinus), which almost always inhabit different countries or occupy different stations. We will now consider some other modes in which natural selection will act, to adapt organisms to changed conditions.

It is found, that, in domestic animals and cultivated plants, variations occurring at any one period of life reappear in the offspring at the same period, and can be perpetuated and increased by selection without modifying other parts of the organisation. Thus, variations in the caterpillar or the cocoon of the silkworm, in the eggs of poultry, and in the seeds or young shoots of many culinary vegetables, have been accumulated till those parts have become greatly modified and, for man's purposes, improved. Owing to this fact it is easy for organisms to become so modified as to avoid dangers that occur at any one period of life. Thus it is that so many seeds have become adapted to various modes of dissemination or protection. Some are winged, or have down or hairs attached to them, so as to enable them to be carried long distances in the air; others have curious hooks and prickles, which cause them to be attached firmly to the fur of mammals or the feathers of birds; while others are buried within sweet or juicy and brightly coloured fruits, which are seen and devoured by birds, the hard smooth seeds passing through their bodies in a fit state for germination. In the struggle for existence it must benefit a plant to have increased means of dispersing its seeds, and of thus having young plants produced in a greater variety of soils, aspects, and surroundings, with a greater chance of some of them escaping their numerous enemies and arriving at maturity. The various differences referred to would, therefore, be brought about by variation and survival of the fittest, just as surely as the length and quality


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V of cotton on the seed of the cotton-plant have been increased by man's selection.

The larvæ of insects have thus been wonderfully modified in order to escape the numerous enemies to whose attacks they are exposed at this period of their existence. Their colours and markings have become marvellously adapted to conceal them among the foliage of the plant they live upon, and this colour often changes completely after the last moult, when the creature has to descend to the ground for its change to the pupa state, during which period a brown instead of a green colour is protective. Others have acquired curious attitudes and large ocelli, which cause them to resemble the head of some reptile, or they have curious horns or coloured ejectile processes which frighten away enemies; while a great number have acquired secretions which render them offensive to the taste of their enemies, and these are always adorned with very conspicuous markings or brilliant colours, which serve as a sign of inedibility and prevent their being needlessly attacked. This, however, is a portion of the very large subject of organic colour and marking, which will be fully discussed and illustrated in a separate chapter.

In this way every possible modification of an animal or plant, whether in colour, form, structure, or habits, which would be serviceable to it or to its progeny at any period of its existence, may be readily brought about. There are some curious organs which are used only once in a creature's life, but which are yet essential to its existence, and thus have very much the appearance of design by an intelligent designer. Such are, the great jaws possessed by some insects, used exclusively for opening the cocoon, and the hard tip to the beak of unhatched birds used for breaking the eggshell. The increase in thickness or hardness of the cocoons or the eggs being useful for protection against enemies or to avoid accidents, it is probable that the change has been very gradual, because it would be constantly checked by the necessity for a corresponding change in the young insects or birds enabling them to overcome the additional obstacle of a tougher cocoon or a harder eggshell. As we have seen, however, that every part of the organism appears to be varying independently, at the same time, though to different Rh


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 amounts, there seems no reason to believe that the necessity for two or more coincident variations would prevent the required change from taking place.

Since species are continually undergoing modifications giving them some superiority over other species or enabling them to occupy fresh places in nature, it may be asked—Why do any low forms continue to exist? Why have they not long since been improved and developed into higher forms? The answer, probably, is, that these low forms occupy places in nature which cannot be filled by higher forms, and that they have few or no competitors; they therefore continue to exist. Thus, earthworms are adapted to their mode of life better than they would be if more highly organised. So, in the ocean, the minute foraminifera and infusoria, and the larger sponges and corals, occupy places which more highly developed creatures could not fill. They form, as it were, the base of the great structure of animal life, on which the next higher forms rest; and though in the course of ages they may undergo some changes, and diversification of form and structure, in accordance with changed conditions, their essential nature has probably remained the same from the very dawn of life on the earth. The low aquatic diatomaceæ and confervæ, together with the lowest fungi and lichens, occupy a similar position in the vegetable kingdom, filling places in nature which would be left vacant if only highly organised plants existed. There is, therefore, no motive power to destroy or seriously to modify them; and they have thus probably persisted, under slightly varying forms, through all geological time.

So soon; however, as we approach the higher and more fully developed groups, we see indications of the often repeated extinction of lower by higher forms. This is shown by the great gaps that separate the mammalia, birds, reptiles, and fishes from each other; while the lowest forms of each are always few in number and confined to limited areas. Such


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V are the lowest mammals—the echidna and ornithorhynchus of Australia; the lowest birds—the apteryx of New Zealand and the cassowaries of the New Guinea region; while the lowest fish—the amphioxus or lancelet, is completely isolated, and has apparently survived only by its habit of burrowing in the sand. The great distinctness of the carnivora, ruminants, rodents, whales, bats, and other orders of mammalia; of the accipitres, pigeons, and parrots, among birds; and of the beetles, bees, flies, and moths, among insects, all indicate an enormous amount of extinction among the comparatively low forms by which, on any theory of evolution, these higher and more specialised groups must have been preceded.

We have already seen that, when there is no change in the physical or organic conditions of a country, the effect of natural selection is to keep all the species inhabiting it in a state of perfect health and full development, and to preserve the balance that already exists between the different groups of organisms. But, whenever the physical or organic conditions change, to however small an extent, some corresponding change will be produced in the flora and fauna, since, considering the severe struggle for existence and the complex relations of the various organisms, it is hardly possible that the change should not be beneficial to some species and hurtful to others. The most common effect, therefore, will be that some species will increase and others will diminish; and in cases where a species was already small in numbers a further diminution might lead to extinction. This would afford room for the increase of other species, and thus a considerable readjustment of the proportions of the several species might take place. When, however, the change was of a more important character, directly affecting the existence of many species so as to render it difficult for them to maintain themselves without some considerable change in structure or habits, that change would, in some cases, be brought about by variation and natural selection, and thus new varieties or new species might be formed. We have to consider, then, which


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 are the species that would be most likely to be so modified, while others, not becoming modified, would succumb to the changed conditions and become extinct.

The most important condition of all is, undoubtedly, that variations should occur of sufficient amount, of a sufficiently diverse character, and in a large number of individuals, so as to afford ample materials for natural selection to act upon; and this, we have seen, does occur in most, if not in all, large, wide-ranging, and dominant species. From some of these, therefore, the new species adapted to the changed conditions would usually be derived; and this would especially be the case when the change of conditions was rather rapid, and when a correspondingly rapid modification could alone save some species from extinction. But when the change was very gradual, then even less abundant and less widely distributed species might become modified into new forms, more especially if the extinction of many of the rarer species left vacant places in the economy of nature.

An excellent example of how a limited group of species has been able to maintain itself by adaptation to one of these "vacant places" in nature, is afforded by the curious little birds called dippers or water-ouzels, forming the genus Cinclus and the family Cinclidæ of naturalists. These birds are something like small thrushes, with very short wings and tail, and very dense plumage. They frequent, exclusively, mountain torrents in the northern hemisphere, and obtain their food entirely in the water, consisting, as it does, of water-beetles, caddis-worms and other insect-larvæ, as well as numerous small freshwater shells. These birds, although not far removed in structure from thrushes and wrens, have the extraordinary power of flying under water; for such, according to the best observers, is their process of diving in search of their prey, their dense and somewhat fibrous plumage retaining so much air that the water is prevented from touching their bodies or even from wetting their feathers to any great extent. Their powerful feet and long curved claws enable them to hold on to stones at the bottom, and thus to retain their position while picking up insects, shells,


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v etc. As they frequent chiefly the most rapid and boisterous torrents, among rocks, waterfalls, and huge boulders, the water is never frozen over, and they are thus able to live during the severest winters. Only a very few species of dipper are known, all those of the old world being so closely allied to our British bird that some ornithologists consider them to be merely local races of one species; while in North America and the northern Andes there are two other species.

Here then we have a bird, which, in its whole structure, shows a close affinity to the smaller typical perching birds, but which has departed from all its allies in its habits and mode of life, and has secured for itself a place in nature where it has few competitors and few enemies. We may well suppose, that, at some remote period, a bird which was perhaps the common and more generalised ancestor of most of our thrushes, warblers, wrens, etc., had spread widely over the great northern continent, and had given rise to numerous varieties adapted to special conditions of life. Among these some took to feeding on the borders of clear streams, picking out such larvae and molluscs as they could reach in shallow water. When food became scarce they would attempt to pick them out of deeper and deeper water, and while doing this in cold weather many would become frozen and starved. But any which possessed denser and more hairy plumage than usual, which was able to keep out the water, would survive; and thus a race would be formed which would depend more and more on this kind of food. Then, following up the frozen streams into the mountains, they would be able to live there during the winter; and as such places afforded them much protection from enemies and ample shelter for their nests and young, further adaptations would occur, till the wonderful power of diving and flying under water was acquired by a true land-bird.

That such habits might be acquired under stress of need is rendered highly probable by the facts stated by the well-known American naturalist, Dr. Abbott. He says that "the water-thrushes (Seiurus sp.) all wade in water, and often, seeing minute mollusca on the bottom of the stream, plunge both head and neck beneath the surface, so that often, for


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 several seconds, a large part of the body is submerged. Now these birds still have the plumage pervious to water, and so are liable to be drenched and sodden; but they have also the faculty of giving these drenched feathers such a good shaking that flight is practicable a moment after leaving the water. Certainly the water-thrushes (Seiurus ludovicianus, S. auricapillus, and S. noveboracensis) have taken many preliminary steps to becoming as aquatic as the dipper; and the winter-wren, and even the Maryland yellow-throat are not far behind."

Another curious example of the way in which species have been modified to occupy new places in nature, is afforded by the various animals which inhabit the water-vessels formed by the leaves of many epiphytal species of Bromelia. Fritz Müller has described a caddis-fly larva which lives among these leaves, and which has been modified in the pupa state in accordance with its surroundings. The pupæ of caddis-flies inhabiting streams have fringes of hair on the tarsi to enable them to reach the surface on leaving their cases. But in the species inhabiting bromelia leaves there is no need for swimming, and accordingly we find the tarsi entirely bare. In the same plants are found curious little Entomostraca, very abundant there but found nowhere else. These form a new genus, but are most nearly allied to Cythere, a marine type. It is believed that the transmission of this species from one tree to another must be effected by the young crustacea, which are very minute, clinging to beetles, many of which, both terrestrial and aquatic, also inhabit the bromelia leaves; and as some water-beetles are known to frequent the sea, it is perhaps by these means that the first emigrants established themselves in this strange new abode. Bromeliæ are often very abundant on trees growing on the water's edge, and this would facilitate the transition from a marine to an arboreal habitat. Fritz Müller has also found, among the bromelia leaves, a small frog bearing its eggs on its back, and having some other peculiarities of structure. Several beautiful little aquatic plants of the genus Utricularia or bladder-wort also inhabit bromelia leaves; and these send runners out to neighbouring plants and thus spread themselves with great rapidity.