In birds also the similarities to our own familiar songsters first strike us, though the differences are perhaps really greater than in the quadrupeds. We see thrushes and wrens, tits and finches, and what seem to be warblers and flycatchers and starlings in abundance; but a closer examination shows the ornithologist that what he took for the {50} latter are really quite distinct, and that there is not a single true flycatcher of the family Muscicapidae, or a single starling of the family Sturnidae in the whole continent, while there are very few true warblers (Sylviidae), their place being taken by the quite distinct families Mniotiltidae or wood-warblers, and Vireonidae or greenlets. In like manner the flycatchers of America belong to the totally distinct family of tyrant-birds, Tyrannidae, and those that look like starlings to the hang-nests, Icteridae; and these four peculiar families comprise about a hundred and twenty species, and give a special character to the ornithology of the country. Add to these such peculiar birds as the mocking thrushes (Mimus), the blue jays (Cyanocitta), the tanagers, the peculiar genera of cuckoos (Coccygus and Crotophaga), the humming-birds, the wild turkeys (Meleagris), and the turkey-buzzards (Cathartes), and we see that if there is any doubt as to the mammals of North America being sufficiently distinct to justify the creation of a separate region, the evidence of the birds would alone settle the question. The reptiles, and some others of the lower animals, add still more to this weight of evidence. The true rattlesnakes are highly characteristic, and among the lizards are several genera of the peculiar American family, the Iguanidae. Nowhere in the world are the tailed batrachians so largely developed as in this region, the Sirens and the Amphiumidae forming two peculiar families, while there are nine peculiar genera of salamanders, and two others allied respectively to the Proteus of Europe and the Sieboldia or giant salamander of Japan. There are seven peculiar families and about thirty peculiar genera of fresh-water fishes; while the fresh-water molluscs are more numerous than in any other region, more than thirteen hundred species and varieties having been described.