“In South America, according to Roulin, dogs belonging to a breed that has long been trained to the dangerous chase of the peccary, when taken for the first time into the woods, know the tactics to adopt quite as well as the old dogs, and that without any instruction. Dogs of other races, and unacquainted with the tactics, are killed at once, no matter how strong they may be. The American greyhound, instead of leaping at the stag, attacks him by the belly, and throws him over, as his ancestors had been trained to do in hunting the Indians. “Thus, then, heredity transmits modification no less than natural instincts.” Should not this rather be—“thus, then, we see that not only older and remoter habits, but habits which have been practised for a comparatively small number of generations, may be so deeply impressed on the individual that they may dwell in his memory, surviving the so-called change of personality which he undergoes in each successive generation”? “There is, however, an important difference to be noted: the heredity of instincts admits of no exceptions, while in that of modifications there are many.” It may be well doubted how far the heredity of instincts admits of no exceptions; on the contrary, it would seem probable that in many races geniuses have from time to time arisen who remembered not only their past experiences, as far as action and habit went, but have been able to rise in some degree above habit where they felt that improvement was possible, and who carried such improvement into further practice, by slightly modifying their structure in the desired direction on the next occasion that they had a chance of dealing with protoplasm at all. It is by these rare instances of intellectual genius (and I would add of moral genius, if many of the instincts and structures of plants and animals did not show that they had got into a region as far above morals—other than enlightened self-interest—as they are above articulate consciousness of their own aims in many other respects)—it is by these instances of either rare good luck or rare genius that many species have been, in all probability, originated or modified. Nevertheless inappreciable modification of instinct is, and ought to be, the rule.