Of all the Vertebrata, we are best acquainted with the mammals. And yet our zoologists differ very widely in respect to the number of their species, though the calculations have been made at very short intervals. For instance, in 1829, Minding computed that the globe contained 1230 species of mammals. In 1832, Charles Bonaparte reduced the total to 1149. Oken estimates it at 1500; and this last figure would seem to be the most probable. Nothing is more curious than the distribution of these 1500 species of mammals, according to the different regions and climates of the globe. Man, according to the best-considered data of science, forms a single family, a single genus, a single species. He alone possesses the power of adapting himself to every climate, and of taking possession of countries the most widely opposite in character. We find him among the snows of the North Pole; we find him under the blazing sun of the Tropics. We find him in the palm-fringed islands of Southern Seas, and in the barren burning waste of the inhospitable Sahara. Considered as an animal who feeds and reproduces himself, he forms alone the order of _Bimana_; so named in opposition to the _Quadrumana_, or apes, who make use of their fore-feet as we do of our two hands. Deprive man of his progressive and transmissible intellect--of those mysterious powers which we call the mind and the soul--and he would become at once the most useless and the most wretched member of the animal world. The warm regions of the old and new continents are the true home and haunt of the apes. They are not sufficiently developed to be able to frequent the temperate or frigid zone. In our European menageries the specimens nearly all die of consumption. The Quadrumana form about one-fourteenth of the whole number of species of Mammalia. The _Carnivora_, characterised by the development of their canine teeth, are spread over the whole globe. They are found in greater numbers in the torrid, however, than in the frigid zone. Their species compose at least one-third of the Mammalia. The _Rodentia_, characterised by the development of the incisors, are wanting in Polynesia, and are rare in Australia. They are found in their maximum number in the torrid zone. Like the Carnivora, they form about one-third of the Mammalia. The _Ruminantia_, remarkable for the development of their digestive apparatus, are distributed into 165 species, representing something less than one-ninth of the Mammalia. Africa, of all the continents, is richest in the Ruminants. The _Marsupialia_, so strangely distinguished by the membranous pouch in which they enclose their young, belong to America, and especially Australia. At present about 123 species are known, or a little more than one-thirteenth of the Mammalia.