brity of our atmosphere," their non-existence presupposes also the non-existence of their pestilential food.

Those who argue that, because the food of the herbivorous animal is chemically the same as the carnivorous, therefore nothing is gained to the amount of animal life and enjoyment by the existence of carnivora, unless the stock of vegetable food failed from the superfecundity of animal life, appear to overlook certain facts important to a correct decision. They seem to forget that, if vegetables have a chemistry, animals have a chemistry of their own also; that, although vegetable is the ultimate solid support of animal life, yet animals drink and breathe as well as eat; and that drinking and breathing are the means of growth. The problem is not merely, Given a certain surface of earth, and a certain amount of vegetable life, to support and determine the greatest amount of animal life; but, Given both these, and an ocean of air and of water in addition. The animal draws from these latter sources as copiously as the vegetable. And the consequence is, that the quantity of animal matter in existence is incomparably greater than the amount of vegetable matter would account for. And the obvious inference is, that a far greater variety and amount of animal life is supportable by employing this vast quantity of animal substance as food, than if it were all wasted, and animal life were sustained by vegetable nourishment alone. The system of prey is only incidental to this greater question. If it be true, that the same animal seized as prey, affords a much larger quantity of nourishment than it would if it had been left to waste away in sickness and death; if the sudden and rapid multiplication of insect life would in some instance strip a district of its vegetable clothing were it not kept in check by an insectivorous provision; and if, as I have instanced in the case of the ant and the aphides, (other illustrations might be easily adduced,) their destruction for food does not cancel the previous fact of their existence and enjoyment, the conclusion is fully warranted, that it is more consistent with the greatest amount of enjoyment that a certain proportion of animal food should be animated and be filled with pleasure until it is wanted than it should never have existed.

NOTE F, p. 218,

On the presumed influences of climate, food, and hybridization, the following observations are valuable, from "Ornamental and

Domestic poultry; their History and Management." By the Rev. E. S. Dixon, M. A.

"Some very important speculations respecting organic life, and the history of the animated races now inhabiting this planet, are closely connected with the creatures we retain in domestication, and can scarcely be studied so well in any other field. Poultry, living under our very roof, and, by the rapid succession of their generations, affording a sufficient number of instances for even the short life of man to give time to take some cognisance of their progressive succession,- poultry afford the best possible subjects for observing the transmission or interruption of hereditary forms and instincts. I shall, no doubt, at the first glance, be pronounced rash, as soon as I am perceived to quit the plain task of observing, for the more adventurous one of speculating upon what I have observed. I can only say that the conclusion to which I have arrived respecting what is called the 'origin' of our domestic races, has been, to my own mind, irresistible, having begun the investigation with a bias towards what I must call the wild theory, although so fashionable of late, that our tame breeds or varieties are the result of cross breeding between undomesticated animals, fertile inter se. It will be found, I imagine, on strict inquiry, that the most careful breeding will only fix and make prominent peculiar features or points that are observed in certain families of the same aboriginal species, or sub-species, -no more: and that the whole world might be challenged to bring evidence (such as would be admitted in an English court of justice) that any permanent intermediate variety of bird or animal, that would continue to reproduce offspring like itself, and not reverting to either original type, had been originated by the crossing of any two wild species. Very numerous instances of the failure of such experimental attempts might be adduced. The difficulty under which science labors in pursuing this inquiry, is much increased by the mystery in which almost all breeders have involved their proceedings even if they have not purposely misled those who have endeavored to trace the means employed. As to the great question of the Immutability of Species, so closely allied to the investigation of the different varieties of poultry, as far as my own limited researches have gone and they have been confined almost entirely to birds under the influence of man - they have led me to the conclusion that even sub-species and varieties are much more permanent, independent, and ancient than is currently believed at the present day. This result has been to me unavoidable, as well as unexpected; for, as above mentioned, I started with a great idea of the

powerful transmuting influence of time, changed climate, and increased food. My present conviction is, that the diversities which we see in even the most nearly allied species of birds are not produced by any such influences, nor by hybridization; but that each distinct species, however nearly resembling any other, has been produced by a Creative Power: I am even disposed to adopt this view towards many forms that are usually considered ás mere varieties. As far as I have been able to ascertain facts, hybrids that are fertile are even then saved from being posterityless (to coin a word) only by their progeny rapidly reverting to the type of one parent or the other; so that no intermediate race is founded. Things very soon go on as they went before, or they cease to go on at all. This is the case with varieties also, and is well known to breeders as one of the most inflexible difficulties they have to contend with, called by them 'crying back.' This circumstance first led me to suspect the permanence and antiquity of varieties, and even of what are called 'improvements' and new breeds.' Half of the mongrels that one sees are only transition-forms, passing back to the type of one or other original progenitor. At least, my eye can detect such to be frequently the apparent fact in the case of Domestic Fowls. Any analogies from plants must be cautiously applied to animals; but even in the vegetable kingdom the number and reproductive power of hybrids is apparently greater than it really is, owing to the facility of propagation by extension, by which means a perfectly sterile individual can be multiplied and kept in existence for many hundred years; whereas a half-bred bird or animal would, in a short time, disappear and leave no trace. I have not met with one authenticated fact of the race of pheasants having been really and permanently incorporated with fowls, so as to originate a mixed race capable of continuation with itself; but with many that prove the extreme improbability of such a thing happening."

NOTE G, p. 223.

"Some years ago," (says Professor Schleiden, in "The Plant: a Biography,") "I was very intimate with the directing physician of a large lunatic asylum, and I used industriously to avail myself of the liberty I thus obtained, to visit at will the house and its inhabitants. One morning I entered the room of a madman, whose constantly varying hallucinations especially interested me. I found him crouching down by the stove, watching, with close attention, a saucepan, the contents of which he was carefully stir

ring. At the noise of my entrance, he turned round, and, with a face of the greatest importance, whispered, 'Hush, hush! don't disturb my little pigs; they will be ready directly. Full of curiosity to know whither his diseased imagination had now led him, I approached nearer. You see,' said he, with the mysterious expression of an alchemist, 'here I have black-puddings, pigs' bones and bristles, in the saucepan everything that is necessary -we only want the vital warmth, and the young pig will be ready made again."" This is hardly a caricature of certain speculatists. "Organism" (says Oken) "is galvanism residing in a thoroughly homogeneous mass. ** A galvanic pile pounded into atoms must become alive. In this manner, nature brings forth organic bodies" !!

NOTE H, p. 231.

"The geographical distribution of organic groups in space (says Mr. Strickland in his work on "The Dodo and its Kindred") "is a no less interesting result of science than their geological succession in time. We find a special relation to exist between the structures of organized bodies and the districts of the earth's surface which they inhabit. Certain groups of animals or vegetables, often very extensive, and containing a multitude of genera or of species, are found to be confined to certain continents and their circumjacent islands. In the present state of science we must be content to admit the existence of this law, without being able to enunciate its preamble. It does not imply that organic distribution depends on soil and climate; for we often find a perfect identity of these conditions in opposite hemispheres and in remote continents, whose faunæ and floræ are almost wholly diverse. It does not imply that allied but distinct organisms have been educed by generation or spontaneous development from the same original stock; for (to pass over other objections) we find detached volcanic islets which have been ejected from beneath the ocean, (such as the Galapagos, for instance,) inhabited by terrestrial forms allied to those of the nearest continent, though hundreds of miles distant, and evidently never connected with them. But this fact may indicate that the Creator in forming new organisms to discharge the functions required from time to time by the ever vacillating balance of Nature, has thought fit to preserve the regularity of the System by modifying the types of structure already established in the adjacent localities, rather than to proceed per saltum by introducing forms of more foreign aspect."

INDEX.