34 BULLETIN 199, UNITED STATES NATIONAL MUSEUM 



CHRYSEMYS PICTA BELLII (Gray) 



Emys hellii Gray, Synopsis reptilium . . . , 1831, p. 31. 



Chrysemys picta hellii, Bishop and Schmidt, Publ. Field Mus. Nat. Hist., zool. 

 ser., vol. 18, 1931, p. 136. 



Type. — Lost; originally in Brit. Mus. 



Type locality. — Unknown, here restricted to Manhattan, Kans. 



Range. — Western Illinois to Washington and British Columbia, 

 south on the east of the Cascade Mountains to northern Chihuahua 

 and southern Texas. Recorded only from the state of Chihuahua: 

 Rio Santa Maria, near Progreso. 



Genus TERRAPENE Merrem 



Terrapene Merrem, Tentamen systematis amphibiorum, 1820, p. 27. — Ditmars, 

 Zoologica, vol. 17, 1934, pp. 1-44, figs. 1-41. 



Type. — Testudo clausa Gm.e\m== Terrapene Carolina (Linnaeus). 



Range. — North America east of the Rocky Mountains and Arizona, 

 south to Yucatdn and Nayarit. 



Species. — Eleven species and subspecies are recognized at present, 

 six in Mexico. 



KEY TO MEXICAN SPECIES OF TERRAPENE 



1. Plastron with a conspicuous and well-defined pattern of yellow lines on a dark 



background (or dark lines on a yellow background) ornata (p. 36) 



Plastron without a lined pattern, either uniform or suffused here and there 

 with dark color 2 



2. Pattern of carapace consisting of small, round or ovoid yellow dots 1.5-2 mm. 



in diameter, separated from each other by an average distance of 4 mm. 



klauberi (p. 35) 

 Pattern not so 3 



3. Width of carapace 65-68 percent length of carapace, average 66 percent; height 



of shell 40-45 percent length of carapace; 4 rear claws; carapace horn-colored, 



without dark borders at sutures coahuila (p. 36) 



Width of carapace 68-79 percent length of carapace, average about 73 percent; 

 height of shell 45-58 percent length of carapace, average 51 percent; rear 

 claws 3 or 4; carapace either marked with yellow or horn-colored, but sutures 

 always broadly margined with dark color 4 



4. No notch at apex of upper jaws; 4 rear claws nelsoni (p. 35) 



Apex of upper jaw notched; rear claws 3 or 4 5 



5. Rear claws always (so far as known) 4 mexicana yucatana (p. 35) 



Rear claws generally 3 (81 percent of '^2 specimens). 



mexicana mexicana (p. 34) 



TERRAPENE MEXICANA MEXICANA (Gray) 



Cistudo (Onychotria) mexicana Gray, Proc. Zool. Soc. London, 1848 (Feb. 1849), 



vol. 16, pp. 16-17, pi. 2. 

 Cistudo mexicana, Gray, Catalogue of shield reptiles in the British Museum, pt. 



1, Testudinata, 1855, p. 40. 

 Onychotria mexicana, Ducfes, La Naturaleza, ser. 2, vol. 1, 1888, pp. 107-108. 

 Cistudo Carolina var. mexicana, Boulenger, Catalogue of the chelonians, rhyn- 



chocephalians and crocodiles in the British Museum, 1889, p. 118. 



