"As a zoologist of old standing," he felt bound to protest against the abuse of a term--the struggle for existence--borrowed from zoology, or, at least, against overrating its importance. Zoology, he said, and those sciences which deal with man, continually insist upon what they call the pitiless law of struggle for existence. But they forget the existence of another law which may be described as the law of mutual aid, which law, at least for the animals, is far more essential than the former. He pointed out how the need of leaving progeny necessarily brings animals together, and, "the more the individuals keep together, the more they mutually support each other, and the more are the chances of the species for surviving, as well as for making further progress in its intellectual development." "All classes of animals," he continued, "and especially the higher ones, practise mutual aid," and he illustrated his idea by examples borrowed from the life of the burying beetles and the social life of birds and some mammalia. The examples were few, as might have been expected in a short opening address, but the chief points were clearly stated; and, after mentioning that in the evolution of mankind mutual aid played a still more prominent part, Professor Kessler concluded as follows:-- "I obviously do not deny the struggle for existence, but I maintain that the progressive development of the animal kingdom, and especially of mankind, is favoured much more by mutual support than by mutual struggle.... All organic beings have two essential needs: that of nutrition, and that of propagating the species. The former brings them to a struggle and to mutual extermination, while the needs of maintaining the species bring them to approach one another and to support one another. But I am inclined to think that in the evolution of the organic world--in the progressive modification of organic beings--mutual support among individuals plays a much more important part than their mutual struggle."(4) The correctness of the above views struck most of the Russian zoologists present, and Syevertsoff, whose work is well known to ornithologists and geographers, supported them and illustrated them by a few more examples. He mentioned sone of the species of falcons which have "an almost ideal organization for robbery," and nevertheless are in decay, while other species of falcons, which practise mutual help, do thrive. "Take, on the other side, a sociable bird, the duck," he said; "it is poorly organized on the whole, but it practises mutual support, and it almost invades the earth, as may be judged from its numberless varieties and species."