First in order of importance comes the fact that not only are there uniformly transmitted from an organism to its offspring, those traits of structure which distinguish the class, order, genus, and species; but also those which distinguish the variety. We have numerous cases, among both plants and animals, where, by natural or artificial conditions, there have been produced divergent modifications of the same species; and abundant proof exists that the members of any one sub-species habitually transmit their distinctive peculiarities to their descendants. Agriculturists and gardeners can furnish unquestionable illustrations. Several varieties of wheat are known, of which each reproduces itself. Since the potato was introduced into England there have been formed from it a number of sub-species; some of them differing greatly in their forms, sizes, qualities, and periods of ripening. Of peas, also, the like may be said. And the case of the cabbage-tribe is often cited as showing the permanent establishment of races which have diverged widely from a common stock. Among fruits and flowers the multiplication of kinds, and the continuance of each kind with certainty by agamogenesis, and to some extent by gamogenesis, might be exemplified without end. From all sides evidence may be gathered showing a like persistence of varieties among animals. We have our distinct breeds of sheep, our distinct breeds of cattle, our distinct breeds of horses: each breed maintaining its characteristics. The many sorts of dogs which, if we accept the physiological test, we must consider as all of one species, show us in a marked manner the hereditary transmission of small differences--each sort, when kept pure, reproducing itself not only in size, form, colour, and quality of hair, but also in disposition and speciality of intelligence. Poultry, too, have their permanently-established races. And the Isle of Man sends us a tail-less kind of cat. Even in the absence of other evidence, that which ethnology furnishes would suffice. Grant them to be derived from one stock, and the varieties of man yield proof upon proof that non-specific traits of structure are bequeathed from generation to generation. Or grant only their derivation from several stocks, and we still have, between races descended from a common stock, distinctions which prove the inheritance of minor peculiarities. Besides seeing the Negroes continue to produce Negroes, copper-coloured men to produce men of a copper colour, and the fair-skinned races to perpetuate their fair skins--besides seeing that the broad-faced and flat-nosed Calmuck begets children with broad faces and flat noses, while the Jew bequeaths to his offspring the features which have so long characterized Jews; we see that those small unlikenesses which distinguish more nearly-allied varieties of men, are maintained from generation to generation. In Germany, the ordinary shape of skull is appreciably