Many striking illustrations of social life could be taken from the life of the reindeer, and especially of that large division of ruminants which might include the roebucks, the fallow deer, the antelopes, the gazelles, the ibex, and, in fact, the whole of the three numerous families of the Antelopides, the Caprides, and the Ovides. Their watchfulness over the safety of their herds against attacks of carnivores; the anxiety displayed by all individuals in a herd of chamois as long as all of them have not cleared a difficult passage over rocky cliffs, the adoption of orphans; the despair of the gazelle whose mate, or even comrade of the same sex, has been killed; the plays of the youngsters, and many other features, could be mentioned. But perhaps the most striking illustration of mutual support is given by the occasional migrations of fallow deer, such as I saw once on the Amur. When I crossed the high plateau and its border ridge, the Great Khingan, on my way from Transbaikalia to Merghen, and further travelled over the high prairies on my way to the Amur, I could ascertain how thinly-peopled with fallow deer these mostly uninhabited regions are.(19) Two years later I was travelling up the Amur, and by the end of October reached the lower end of that picturesque gorge which the Amur pierces in the Dousse-alin (Little Khingan) before it enters the lowlands where it joins the Sungari. I found the Cossacks in the villages of that gorge in the greatest excitement, because thousands and thousands of fallow deer were crossing the Amur where it is narrowest, in order to reach the lowlands. For several days in succession, upon a length of some forty miles up the river, the Cossacks were butchering the deer as they crossed the Amur, in which already floated a good deal of ice. Thousands were killed every day, and the exodus nevertheless continued. Like migrations were never seen either before or since, and this one must have been called for by an early and heavy snow-fall in the Great Khingan, which compelled the deer to make a desperate attempt at reaching the lowlands in the east of the Dousse mountains. Indeed, a few days later the Dousse-alin was also buried under snow two or three feet deep. Now, when one imagines the immense territory (almost as big as Great Britain) from which the scattered groups of deer must have gathered for a migration which was undertaken under the pressure of exceptional circumstances, and realizes the difficulties which had to be overcome before all the deer came to the common idea of crossing the Amur further south, where it is narrowest, one cannot but deeply admire the amount of sociability displayed by these intelligent animals. The fact is not the less striking if we remember that the buffaloes of North America displayed the same powers of combination. One saw them grazing in great numbers in the plains, but these numbers were made up by an infinity of small groups which never mixed together. And yet, when