This action leads us to a consideration of the behavior of animals toward companions in distress. “Herbivorous animals at such times will trample and gore the distressed one to death. In the case of wolves and other savage-tempered carnivorous species the distressed fellow is frequently torn to pieces and devoured on the spot.” If any one will be bold enough to claim in this case that this habit has been acquired because of advantage to the pack, _i.e._ if it be imagined that the pack gains more by feeding on a weak member than by letting him take his chances of recovery, it may be pointed out in reply that cattle also destroy their weak or injured, but do not devour them, and the same statement holds for birds, where the same instinct has often been observed. Romanes has suggested that the instinct of destroying the weak or injured members is of use because such members are a source of danger to the rest of the herd; but Hudson points out that it is not so much the weak and sickly members of the herd that are attacked in this way, as those that are injured, and concludes, “the instinct is not only useless, but actually detrimental.” He suggests that these “wild abnormal movements of social animals” are a sort of aberration, so “that in turning against a distressed fellow they oppose themselves to the law of being.” Yet whether we gain anything by calling this action aberrant or abnormal, the important fact remains that it is a definite response under certain external conditions, and is shown by all the individuals of the species. The preceding illustrations of reactions that go to make up the so-called instincts of animals may be separated into those that are essential to the life of the individual or of the race, those that are of some apparent use, although not absolutely essential, and a few of no use at all, and fewer still that appear to be even injurious. If the latter reactions take place only rarely, as appears often to be the case, they are not sufficiently harmful to cause the destruction of the race. The evidence points to the conclusion, I believe, that the origin of these tropisms and instincts cannot be accounted for on the ground of their benefit to the individual or to the race; and it does not seem reasonable to make up one explanation for the origin of those that are essential, and another for those that are of little use or even of no use at all.