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the corresponding groups in other circles, so as to give at least an air of probability to their scheme.* But our author, being “only a general student,” submits to no such drudgery. He does not pretend to show that his hypothesis of stirpes is consistent with the facts, or with any of them. All the information which he condescends to give us, is the following remarkably definite and satisfactory statement !
“ The lines or stirpes have all of them peculiar characteristics, which persist throughout the various grades of being passed through : one presenting carnivorous, another gentle and innocent animals, and so on.”
“There is a unity, in all instances, in the moral as well as physical characters of the various members of one stirps : we only see it advancing from low to high characters, just as we see the fætus of a high animal passing through various inferior stages before it reaches its proper mature character.”—Explanations, pp. 49, 53.
It would really have been kind in him to enlighten us in regard to our own ancestry a few steps beyond those novi homines, the chimpanzes, by informing us what reptile, fish, or insect, has moral and physical characters in unity with ours, even if he found it difficult to trace out the respectable lineage, by the blazons of fossil heraldry, to the Adam and Eve of his own peculiar Genesis, a pair of omnivorous animalcules. The only advantage which he can derive from this new hypothesis, is to make it more difficult for his opponents to prove a negative : a thing which they are no more required to do, in the present case, than if he had asserted that the moon was made of green cheese. It is the après coup of a retreating enemy, who makes a feint to show a bold front while he abandons his ground. The facility with which he shifts his position, proves him to be an adroit tactician; and to possess in its highest development the trait which Napoleon attributed to this writer's countryinen-inability to discover when he is beaten.
We will now look the hypothesis of development by transmutation, whether in one line or many, more directly in the face. The facts adduced in support of the doctrine are the common stock-in-trade of the atheistic school of physiologists ; and we must admit that in his operations with this stock the writer exhibits one proof at least of talent—the ability to do a large business with a small capital. He repeats the old story of the cabbage and cauliflower, of oats changing to rye, and forests of pine to beach and poplar; appeals to what he calls the abortive or rudimental organs of animals, to the similarity of the skeletons of the vertebrata, to the successive
* See Macleay's Hora Entomologice and Swainson’s Classification of Animals.
stages in the progress of the mammalian fætus, to the changes produced in men and puppies by external conditions and modes of life, and concludes from all these that men are the offspring of monkeys; and that in two generations, by one incubation and one gestation, a rat may be hatched from a goose's egg! The evidence would have been less equivocal, perhaps, had he informed us that a higher mammal than a rodent had been produced in that manner, without losing, with the bodily form, the mental peculiarities of his grandmother.
We cannot admit that oats have been changed, by cropping down, into barley, rye, and wheat,* until the experimenter will inform us what precautions, if any, were taken to prevent the accidental presence of other grains in the soil. It is well known that seeds will in many instances germinate after passing through the alimentary canal of birds and quadrupeds; and this is undoubtedly the true explanation of the fact that plants, whose seeds are 100 heavy to be transported by winds, often spring up in localities where they had not previously appeared, whenever the condition of the soil becomes favorable to their growth. Thus, for example, when a forest of pines is consumed by fire, the potash, collected during many ages, is restored to the soil, and the germs of other trees, lying dormant in the ground, finding in the potash their appropriate nutriment, are immediately developed.f Again, the similarity of structure observed in the vertebrate animals is an interesting proof that they were formed according to one general plan, and this nobody denies ; but it lends no countenance to the hypothesis that one type can by any possibility be changed into another. The rudimental organs, such as undeveloped feet in serpents, and mammæ in the human male, can be regarded, according to our author, “in no other light than as blemishes or blunders " in a system of creation by the direct agency of God; but they are only“ harmless peculiarities” in a system of creation by law. We cannot comprehend this distinction. He tells us that he goes beyond Lamarck “to a very important point, the original divine conception of all the forms of being which natural laws were only instruments in working out and realizing.”I If these organs are blemishes and blunders which impeach the divine skill in one case, do they not equally impeach the divine foresight in the other? But his assumption, that these organs are useless, is altogethergratuitous. There other
organs in animals of which anatomists have not yet discovered the use ; but it is not their custom to pronounce them blemishes and blunders on account of their own ignorance.
Explanations, p. 79. + Liebig's Agricultural Chemistry, p. 154. Vestiges, p. 177.
The author's capital argument, in support of his doctrine of development, is drawn from the resemblances of the mammalian fætus, in its different stages, to successsive divisions and classes of inferior animals. The brain of a human embryo, for example, first resembles that of an avertebrated animal, then that of a fish, and successively that of a reptile, bird, rodent, ruminant, monkey, and man.
The heart, also, at a certain stage, is like that of an insect; afterward it is two-chambered, like that of a fish; then three-chambered, like that of a reptile ; and finally it becomes a full, four-chambered, mammal heart. The inference which he wishes us to draw from these resemblances, is, that every human being was once a zoophyte, and that he has passed in succession through every grade of being. The discoveries of Tiedemann and Serres warrant no such conclusion. All they prove is this: that some parts of a mammal fætus of the highest order do bear some resemblance, in certain stages of their development, to corresponding parts of some of the inferior animals, at some stage of their development. So the eggs of a duck and hen do bear some resemblance to each other; but still the differences between them are so profound, that nothing but a duck can proceed from the one, and nothing but a chicken from the other. The heart and brain, like all the other organs of the human fætus, are in a state of formation, and consequently imperfect; but they are never anything else than human hearts and brains. In other words, the two-chambered heart of the fætus is not the heart of a fish because it is twochambered ; and the brain of a six months' fætus is not the brain of a calf because it bears some resemblance to a ruminant's brain. However strongly the brain and intermaxillary bone of an eightmonths' child may be “ characteristic of the perfect ape,” yet that child is not born an ape, neither does he grow up an ape. In our author's reasonings upon this point we have an example of a leading trait in his mental character, which has been exposed by his Edinburgh reviewer almost as strongly as in his own writings-a facility in perceiving resemblances, and an almost entire inability either to discover differences, or to comprehend them. This man would believe that snow and frozen carbonic acid are identical, because they have several similar properties; and when he has seen the evening clouds assuming shapes and hues as if
“Built like a temple, where pilasters round
Were set, and Doric pillars overlaid
he has, doubtless, believed that a substantial stone-and-mortar temple was only an exhaled Pandemonium.
Again, it is admitted on all hands that a species, whether animal or vegetable, is capable of a certain degree of modification in accordance with external conditions. Hence, the varieties in the Brassica oleracea, as seen in the cauliflower and red cabbage ; hence, the pointer, poodle, mastiff
, grayhound, and other varieties among dogs; and hence, the Caucasian, Mongolian, American, and African races of the human species. It is nevertheless true that these deviations from standard types are confined within rigorous limits, which, though difficult to define, are never passed over. Not only is there no blending or intermingling of species, but the different varieties return to their original form, whenever the causes in which they originated cease to operate. When the cabbage and cauliflower are removed from the influence of cultivation, they manifest a tendency to return to the bitter sea-side plant. Dogs of different races have run wild in the West India Islands, and have all reverted to their original type, the shepherd's dog.* Mr. Lyell has also mentioned a still stronger case, indicating beyond dispute the reality and persistency of species. “Of the ox, undoubtedly, there are many very distinct races: but the bull Apis, which was led in solemn processions by the Egyptian priests, did not differ from some of those now living. The black cattle that have run wild in America, where there were many peculiarities in the climate not to be found, perhaps, in any part of the old world, and where scarcely a single plant on which they fed was of precisely the same species, instead of altering their form and habits, have actually reverted to the exact likeness of the aboriginal wild cattle of Europe.”+
It is in the face of such facts as these, and a multitude more which might be adduced, that the author of the Vestiges builds up his air-castle of development by transmutation, and alledges that “species is a term, not a fact.” Then, indeed, men may claim sonship to monkeys, and the apish propensity to " play fantastic tricks before high heaven,” evinced by at least one individual of the human family, is satisfactorily accounted for.
But supposing the peculiar conditions favorable for an advance to a higher species, in what manner is the advance made ? Nothing easier. “To protract the gestation over a small space is all that is necessary." True, he can only conjecture how this might be done; “but though this knowledge were never to be clearly attained, it need not much affect the present argument, provided it be satis
Lyell's Geology, vol. I, p. 501.
Principles of Geology, vol. I, p. 502.
factorily proved that there must be some such influence within the range of natural things.” O no! this writer may go on piling assumption upon assumption, like Ossa upon Pelion; and if any one is so skeptical as to ask him for a particle or two of proof, he puts on an air of the most provoking nonchalance, and says :-Never mind about the proof; I will show you that this is within the range of possibilities: or, if it is not now possible, it might have been possible in the geological ages, when possibly the operation of these conditions was more powerful than at present! So, then, it would appear, that when the earth became too cold, and its vegetation too scanty for the shivering and starving mastodons, they were in circumstances so extremely favorable, that some lucky matron among them, by a slightly protracted gestation, produced a species a little higher in the stirps! But what proof has he that there is some such influence within the range of natural things? “Sex is fully ascertained to be a matter of development.” To this the best anatomical authorities give a simple negative; and besides, everybody knows that gestation is not more protracted when a male is produced, than when a female is. But bees have the power of "adjusting the law of development to the production of a particular sex.” In support of this assertion he cites the authority of Huber, whom he entirely misapprehends and misrepresents. So far from supposing that the sex of bees can be adjusted by the bees themselves, Huber not only supposed, but proved, that all the working bees, erroneously called neuters, are females.* But as only one prolific female can exist in a hive, the female larvæ are reared in such a manner that their organs of reproduction are not sufficiently developed to render them fruitful. As the Chinese inclose the feet of their female infants in wooden shoes, so that they never attain their mature size, nor become fitting instruments of locomotion, in like manner the bees, by rearing their female young in narrow cells and feeding them sparingly, prevent the natural development of their ovaries. But the larvæ contiguous to the royal cell do sometimes, by accident, obtain a share of the luxurious viands designed exclusively for her majesty's table, and become prolific workers. For this they pay the forfeit of their lives, being destroyed by the jealous and vindictive queen as soon as she is in a condition to attack them. Bees, therefore, will do nothing for our author, except to convict him of distorting facts and misquoting authorities.
There is one class of phenomena which this writer passes by in
* Nouvelles Observations sur les Abeilles. VOL. VI.-21