128 PHYSICAL GEOGRAPHY. 



SNAKES. 



Black Snake {Coluber constrictor.} Common. 



Pilot Blacksnake Racer {Coluber Allegheniensis]. Rare. 



Milk Snake. House Snake {Coluber eximius). Seen occasion- 

 ally. 



Ring Snake {Coluber punctatu*s}. Seen at long intervals. 



Grass Snake Coluber vernalis}. Rare. 



Coluber testaceus. West Nebraska. 



Water Snake {Trophidonotus sipeciori). Seen at long intervals. 



Striped Snake. Garter Snake {Trophidonotus taenia}. Rare. 



Yellow Bellied Snake {Ttopkidonotus leberis]. South Nebraska^ 



Small Brown Snake {Tropkidonotus DeKayi}. Some seasons 

 rather abundant. 



Little Garter Snake. Ribbon Snake {Leptophis saurita]. Rare. 

 Only in timber. 



Bull Snake {Pituophis melanoleucas\ Common. 



Northern Rattlesnake. Yellow Rattlesnake {Crotalus durissus)~ 

 Sparingly. Most abundant in North Nebraska. 



Michigan Rattlesnake {Crotalophorus miliarius). Rare. 



Western Rattlesnake {Crotalophorus tergeminus). Rare. 



Massasaugua. Prairie Rattlesnake {Crotalophorus Kirtlandt]. 

 Now supposed to be the same as the preceding. Formerly abun- 

 dant.* 



Harlequin Snake {Elaps fulvius). Rare. 



AMPHIBIANS. 



Bullfrog {Rana pipiens). Common. 



Northern Bullfrog {Rana hariconensis]. Rare. 



Spring Frog- {Rana fontinalis). Rather numerous in favorite 

 localities. 



Marsh Frog. Leopard Frog {Rana palustris). Common and 

 abundant. 



Shad Frog. Lopard Frog {Rana kalecina). Common. 



Wood Frog {Rana sylvaticd}. Common in timber along the 

 Missouri. 



Common Toad {Bufo Americanus). Common. 



Missouri Toad {Bufo cognathus]. Occasional. 



Northern Tree Toad {Hyla versicolor). Along the Missouri. 



*For the use of the rattles of the Rattlesnake, see the writer's paper, published in the 

 'American Naturalist," Feb. ,1872. 



