their wing-feathers, and in their tail-feathers. In plants, by the process of bud-variation, have been known to arise, in one generation alone, nectarines from the peach, the red magnum-bonum plum from the yellow magnum-bonum; and the moss rose from the Provence

rose.

An astonishingly great improvement has taken place in the wild carrot, and the parsnip, which, from mere stringy roots that they were, when taken from nature, have developed into great size and delicacy. Gooseberries also have attained great size and weight: The London Gooseberry being seven and eight times the weight of the wild fruit. The fruit of one variety of the Curcurbita pepo, exceeds, in volume, that of another of the same species, which is less cultivated, by more than 2000 fold!

Whatever part of the plant, man values most, that part has been sure to increase surprisingly, in size, in general development, and in quality. If it be the flower, to which man attaches value, the most astonishing improvement, in that character, is seen; while the other parts show little, or no improvement. The same occurs, where it is the fruit, the leaves, or the root, which man prizes.

Varieties of the fowl, of the turkey, of the canarybird, of the duck, and of the goose, have developed top-knots, and reversed head feathers, since they have been taken care of by man. It would be but writing, anew, Darwin's book on "Animals and Plants under Domestication," to record all of the great, and wonderful improvements which have arisen, within a short time, under domestication.

Varieties, or breeds, are formed, in each species, of these variations and improvements. The reader is sufficiently well acquainted with the great improvements which have occurred in the horse, in the sheep, and in cattle, not to need a detailed statement thereof. The Pigeon, however, having displayed, probably, the greatest amount of variation, and as Darwin has not only given the greatest care and attention to this species, but has also used it as the most prominent and striking subject with which to illustrate his view, that divergence of character generates distinct species from the variations of another, a more detailed account of this species, as it exists under man's fostering care, may not be needless.

The progenitor of the pigeons now under domestication, was, Darwin says, the rock pigeon, or Columba livia; which, when redeemed from a state of nature, had not the slightest vestige of many of the characters which now form the striking peculiarities of many of the varieties which have descended from it; and, of those characters, which it had, the development was, by no means, so great and pronounced, as is now seen in many of the varieties.

Darwin says, that so great has been the variation or improvement, with the pigeon, that there are now not less than one hundred and fifty distinct varieties, and subvarieties, descended from this original rock pigeon! The wing feathers, head feathers, and tail feathers, in several varieties, have been greatly changed in character and size. The well known, well marked, upwardly expanded tail, which characterizes the variety,

known as the Fantail, has been developed, since the bird was taken from a state of nature. The oesophagus has attained an enormous size, in the Pouter. A surprisingly large beak marks the Carrier. A great quantity of eye wattle has arisen, and now adorns the Barb. Divergent, and large feathers, along the front of the neck and breast, have appeared, where not even a ruffled feather was discernible before, and distinguish the Turbit. The Jacobin has the feathers so much reversed, along the back of the neck, that they form a hood. These feathers, also, are absent in the common bird, as found under nature. Other varieties have, proportionally to their size, much elongated, or much shortened, heads, necks, legs, tails, wings, bodies; and the proportions of the several characters, have been so much varied, that almost every possible ratio of the development of the species' characters, is to be found among the several varieties. As in the case of other animals, even the bones, and the internal organs, have experienced a marked change in size, number, and other characters.

So great, in fact, has been the range of variation, in this species, that, as Darwin truly remarks, a naturalist, did he not know of the community of descent of these varieties, would be induced to esteem many of them, as distinct species, and a few of them, as even distinct genera.

Judging merely by structural differences, and ignoring the physiological effect which the development or reduction of a character, has upon organisms, there are many other varieties, under domestication, which.

should be regarded as distinct species; and, perhaps, others which a person, so judging, would be not too bold in accounting as belonging to different genera. The argument of Darwin is,

"How possibly can there be fixed species, or immutable species, when the individuals, which represent those species, vary and change so greatly? A species is made up of individuals; and, when those individuals change, the species, also, must necessarily change."

And, again, he argues, if difference in structural build is what alone constitutes the distinction between species, why, then, should not the great differences in structural build, between varieties of what has heretofore been known, or taken, to be one species, be taken as specific distinctions?

Having detailed, at large, these facts of variation, from which Darwin purposes to deduce his theory, the necessity of some inquiry into the natural forces at work in inducing these improvements, occurred to Darwin. Some aspect of these variations—either founded upon a scientific analysis of the phenomena, or, else, gratuitously assumed-had necessarily to be taken for granted as a basis for further research. The question, for instance, whether these variations are amenable to any limit; the question, too, whether it be legitimate to estimate the amount of improvement possible to occur in millions of years, by means of these variations, from the amount of development known to have taken place during the last one hundred years; could not be resolved, unless some view was taken. Darwin admits-aye, explicitly states-that he has not

made such an analysis; but that he has gratuitously assumed a view, the sole warrant of which, is, he urges, that there is no reasonable, opposing view. He candidly admits that he has made no scientific induction from the facts. He contents himself with the fact alone that these improvements do arise. Conscious, that such a treatment of this subject, at the very inception of his problem, is practically to limit all inquiry at the point where the principles of the inductive philosophy especially require an analysis, he concedes that there must be a law governing them, but that it is seemingly inscrutable; and, all that he can say, on the subject, is, that the reason animals and plants vary, or improve, is because they are possessed of "an innate tendency to vary," or because of a “spontaneous variability!" though this, he admits, "is wholly incorrect, and only serves to show our ignorance of the cause of each particular variation."

In science, in law, in the every day affairs of life, it is fair to presume that, in the absence of all evidence, or other presumption to the contrary, anything which occurs regularly, or at frequent intervals, will ever continue so to recur. This presumption is a valid one, always, if all the preceding points in the problem, of which this presumption enters as an element, have been resolved. If, however, there be an hiatus in the chain of reasoning, anterior to the employment of this presumption that things will ever continue as they have been, the presumption is manifestly invalid. In Darwin's problem, he would be fairly entitled to the presumption, that, as variations have ever been occurring, under