chap, xv.] THE NEARCTIC REGION. 133 



Oporornis, genera of wood-warblers, may be considered to be 

 peculiar to this sub-region, since in each case only one of the 

 two species migrates as far as Central America ; while two other 

 genera of the same family, Siurus and Setophaga, as well as the 

 finch genus, Euspiza, do not extend to either of .the western 

 sub-regions. Parus, a genus of tits, comes into the district from 

 the north ; Otocorys, an alpine lark, and Coturniculus, an American 

 finch, from the west ; and such characteristic Nearctic genera as 

 Antrostomus (the whip-poor-will goatsuckers) ; Helminthophaga, 

 Dendrcvca, and Myiodioctes (wood-warblers) ; Vireo (greenlets) ; 

 Dolichonyx (rice-bird) ; Quiscalus (troupial) ; Mcleagris (turkey) ; 

 and Ortyx (American partridge), are wide-spread and abundant. 

 In Mr. J. A. Allen's elaborate and interesting paper on the birds 

 of eastern North America, he enumerates 32 species which breed 

 only in the more temperate portions of this province, and may 

 therefore be considered to be especially characteristic of it. 

 These belong to the following genera : — Turdus, Galcoscoptes, 

 Harporhynchus, Sialia, Dendrmca, Wilsonia, Pyranga, Vireo, 

 Lanivivco, Zophophanes, Coturniculus, Ammodromus, Spizella, 

 Euspiza, Hedymeles, Cyanospiza, Pipilo, Cardinalis, Icterus, 

 Corvus, Centurus, Melanerpcs, Antrostomus, Coccyzus, Ortyx, and 

 Cupidonia. 



Reptiles. — In this class the Eastern States are rich, possessing 

 many peculiar forms not found in other parts of the region. 

 Among snakes it has the genera Farancia and Dimodes belong- 

 ing to the fresh-water snakes (Homalopsidse) ; the South Ameri- 

 can genus Elaps ; and 3 genera of rattlesnakes, Ccnchris, 

 Crotalophorus, and Crotalus. The following genera of snakes 

 are said to occur in the State of New York : — Coluber, Tropido- 

 notus, Leptophis, Calamaria, Heterodon, Trigonocephaly, Crotalus, 

 Psammophis, Helicops, Bhinostoma, Pituophis, and Elaps. 



Among lizards, Chirotes, forming a peculiar family of Amphis- 

 benians, inhabits Missouri and Mexico ; while the remarkable 

 glass-snake, Ophisaurus, belonging to the family Zonuridae, is 

 peculiar to the Southern States; and the South American 

 Sphcerodactylus, one of the gecko family, reaches Florida. 

 Other genera which extend as far north as the State of New 



