its highest development not in man, but in terrestrial mammals otherwise inferior to him—in the dog, for example.
For once, man docs not occupy the apex of the evolutionary pyramid.
Olfactory development, high or low, is linked up with the natural habits of the different species. Thus, mammals which go about on all fours, whose visual outlook is restricted and whose muzzle is near the ground, are the most highly gifted ; those, again, like the seals, porpoises, whales, and walruses, which have reverted from a terrestrial to an aqueous environment, where smell is of less value to them, show poorly developed olfactory organs ; and finally, the apes and man, living habitually above the ground, the former in trees, the latter on his hind legs, and relying chiefly upon vision, also show a decline from the high point reached by four-footed mammalians.
The animals of this kingdom are thus divided into macrosmatic and microsmatic groups. To the latter man belongs, but we must add that his olfactory sense has not yet degenerated so completely as that of certain other species (porpoises, etc.),
It is, of course, common knowledge that in most of the animals we are closely acquainted with the sense of smell is infinitely more delicate an
