Agassiz characterises this kingdom by the existence of one plant and six species of animals, five mammals and one bird. The plant is the Iceland lichen (cenomyce rangiferina). Now, this lichen is so little characteristic of polar regions that it is found in many parts of France, and even in the neighbourhood of Paris at Fontainebleau. M. Decaisne believes that our hares and rabbits live upon it in winter, as the reindeer do in Lapland. Further, the observations recently made in Greenland by the German Polar Expedition, show that in this country, which, of all countries in the Arctic Kingdom, should most readily adapt itself to the conceptions of Agassiz, and which is inhabited by pure-blooded Esquimaux, possesses scarcely one vegetable species which can be said to be peculiar to it, and that a great number of them are found in the Alps, and upon the summits of the Vosges. It is a result of the return of heat after the glacial epoch, the species which resisted it having emigrated in altitude as well as in latitude. In animal species, the white bear and the walrus are really polar. The same may be said of the Greenland seal considered as a species. But as a type we meet with it everywhere; as a genus it inhabits all the seas of Europe. The reindeer inhabited France in the Quaternary epoch; it was living in Germany in Cæsar’s time; it descended yearly to the Caspian Sea during the lifetime of Pallas. The true whale used to visit our coast before it was driven away by man. Finally, at this day, the eider duck builds yearly in Denmark, ten to fifteen degrees south of the Polar circle. Thus, in the six species mentioned by Agassiz as peculiar to his Arctic Kingdom, three at least belong equally to his European Kingdom. Agassiz was certainly more capable than anyone else of nicely characterising the region in question, if it had been possible to do so. He failed, because there is in reality no such thing as a true Arctic fauna. The cause of this lies in the extension of more southern fauna, which become impoverished as they advanced northwards, but change their character very slightly. In reality, this kingdom is broken up into independent provinces, or rather, is connected with regions situated more to the south, and consequently better divided. The Polar region, says Lacordaire, in speaking of insects, is characterised less by the speciality of its products than by their scarcity. All these facts, again, are the consequence of the peopling of the Arctic regions after the glacial epoch.