REPTILES OF THE PACIFIC COAST. 29 



Family 1. TESTUDINID/E. 



This widely distribuLed family oontains a lar(£e num- 

 ber of turtles distinguished from others chiefly by osteo- 

 logical characters. The shell is firmly ossified, and 

 covered with large horny plates of which eleven or twelve 

 are on the plastron. The pectoral plates are in contact 

 with the marginals. The latter are twenty-four or 

 twenty-five in number. The neck can be completely 

 drawn into the shell. Three genera are represented in 

 the area under consideration. 



SYNOPSIS OF GENEEA. 



a. — Feet not club-shaped, webbed; two supracaiidal plates; skin on top 

 of bead not divided into scales. 

 b. — Suture between abdominal plates less than twice lenyth of suture 

 between pectorals ; inguinal plates not wedged in between 



abdominals and marginals Clemmys. — p. 29. 



b^. — Suture between abdominal plates about twice length of suture 

 between pectorals; inguinal plates wedged in between abdomi- 

 nals and marginals Chrysemys. — p. 32. 



a^. — Feet club-shaped, not webbed; one supracaudal plate; skin on top of 

 head divided into scales Gopherus. — p. 35. 



Genus i. CLEMMYS. 



"Clemmys, Wagler, Syst. Amph., 1830, p. 136 (type caspica);" 

 "Ohelopus, Rafin., Atlant. Journ., 1832, p. 64;" "Nanemys, 

 Agassiz, Contr.Nat. Hist. U.S., I, 1857, p. 442" (type guttata); 

 "Calemys, Agassiz, 1. c, p. 443" (type muhlenbergii); "Oly/>- 

 temys, Agassiz, 1. c, p. 443" (type insculpta); Aciinemys, 

 Agassiz, 1. c, p. 444 (type marmorata); "Mauremys, Gray, 

 Proc. Zool. Soc. Loud., 1869, p. 500" (type fuliginosa); 

 "Sacalia, Gray, Suppl. Cat. Sh. Kept. Brit. Mus., 1870, p. .S5;" 

 " Emmenia, Gray, 1. c, p. 38;" ''Eryma, Gray, 1. c, p. 44." 



The shell is broad and low. The plastron is immov- 

 ably united to the carapace by a broad bridge. There 

 is no median ridge on the alveolar surface of the upper 

 jaw parallel to the cutting edge. The internal openings 

 of the nostrils are between the eyes. The fingers and 



