The differences which we call physiological are very numerous; we shall, however, only quote two or three from among the most striking. The principal point, perhaps, is the peculiar smell of the Negro. This is so strong, that it even impregnates for some time a place where a Negro may only have remained for a few hours, and it is so characteristic, that it alone constitutes a grave presumption in matters of slave-trading; for Humboldt has stated concerning the Peruvians what Le Cat and Haller said about the savages of the Antilles, that they could perfectly trace a Negro by scent, thanks to this odour; and it is, at the same time, a new proof of the sensitive perfection of the American race. This odour is quite independent of age, and sometimes is almost insupportable in young children; it is also independent of sweat, and, in fact, of all the means of cleanliness of which a Negro can make use.[146] It is due, according to all appearance, to a secretion from the same glands which, in the white man, give such a peculiar odour to the arm-pits; but this latter is absolutely different from that of the Negro.[147] With regard to this, we must not lose the occasion of noticing one of those contradictions into which monogenists have so often fallen, and, indeed, it could not be otherwise. “The dog does not come from the jackal,” says M. Flourens,[148] “for the jackal has such a peculiar smell, that it does not seem possible that, in this case, the dog should not have preserved some traces of it at least.” Shall we reason in the same manner in order to make a special race of the Negro, and would this monogenist accept it? Another very remarkable physiological peculiarity, and one quite as worthy of being noticed, since it has a certain effect upon physiognomy, upon the _facies_ of a race, is a special mode of standing, consisting in holding oneself in a squatting position, the sole of the foot on the ground, and the thighs bent up against the hams, without the _ischia_ touching the ground. This effect is what Cook called “a monkey countenance.”[149]