VERTEBRATE ANIMALS OF SOUTH CAROLINA. 230 



CHEQUERED TERRAPIN. Chrysemys picta, (Hermann) Grya. 

 CHICKEN TERRAPIN. Chrysemys reticulata, (Bosc) Cope. 

 SPECKLED TORTOISE. Chelopus guttatus, (Schw.) Copo. 

 COMMON BOX TORTOISE. Cistudo Carolina, (I.inn^j Gray. 



TESTUDINID^. 

 GOPHER. Xerobates polyphemus, (Daudin) Cooper. 



ORDER CROCODILIA. CROCODILES. 



An order of lizard-like reptiles, with four legs, fitted for walking or 

 swimming, the feet being webbed. Skin hard and raised into scales, 

 beneath which there are often bony plates. Tail with a series of scales, 

 each crested on the back. Teeth conical,, rootless. Heart with two ven- 

 tricles. 



The Crocodilia, of which the prominent North American species, the 

 alligator, is well known, form a compact group, better represented in 

 past time than at present. They live in sluggish rivers and ponds, and 

 subsist largely on animal food. 



Species of this order are abundant in South America. In North 

 America there are but two recognized species, the alligator and the 

 Florida crocodile {Crocodilus acutus, Cuvier). 



ALLIGATORID^. 

 ALLIGATOR Alligator mississippiensis, Daudin.* 



CLASS AMPHIBIA. AMPHIBIANS. 



A class of cold-blooded vertebrates, closely allied to the fishes. They 

 breathe when young, or throughout life, by external gills. Limbs, when 

 present, present bony elements homologous to those in the limbs of rep- 



*The question has been raised whether there are two species or varieties of alligators 

 in North America, differing in color and other characters. Observations on this point 

 would be of great value.— F. W. T. 



