Natural History.

—Humboldt says, that naturalists already know 56,000 species of cryptogamous and phenerogamous plants, 44,000 insects, 2,500 fishes, 700 reptiles, 4,000 birds, and 500 mammiferæ.

In Europe alone there exists nearly 80 mammiferæ, 400 birds, and 30 reptiles.

There are under this temperate boreal zone 5 times as many species of birds as mammiferæ; 5 times as many compositæ as amentaceous and coniferous plants; 5 times as many leguminous as there are orchideous and euphorbiaceous.