128 PHYSICAL GEOGRAPHY. 



Snakes. 



Black Snake {Coluber constrictor.) Common. 



Pilot Blacksnake Racer [Coluber Altegheniensis). Rare. 



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

 ally. 



Ring Snake {Coluber punctatus). Seen at long intervals. 



Grass Snake Coluber vernalis). Rare. 



Coluber tcstaceus. West Nebraska. 



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



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



Yellow Bellied Snake {Trophidonotus leberis). South Nebraska- 

 Small Brown Snake {Trophidonotus 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 {Croialophorus miliarius). Rare. 



Western Rattlesnake {Croialophorus tergeminus). Rare. 



Massasaugua. Prairie Rattlesnake {Croialophorus Kirtlandi). 

 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 halecina). Common. 



Wood Frog {Rana sylvatica). 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, 1 ' Feb., 1872. 



