CHECKLIST OF THE SNAKES OF MEXICO 161 



30. Median light stripe scarcely distinguishable on any part of body, and 



nowhere more than one scale row wide eques postremus 



Median light stripe covering one and one half to three scale rowB 

 anteriorly, but disappearing completely on posterior part of 

 body sumichrasti fulvus 



31. Ventrals 139 to 157 in males, in females 139 to 147; caudals 58 to 



72 sumichrasti sumichrasti 



Ventrals 155 to 162 in males, 149 to 156 in females; caudals 78 to 

 89 vicinus 



THAMNOPHIS ANGUSTIROSTRIS (Kennicott) " 



Eutaenia angustirostris Kj)nnicott, Proc. Acad. Nat. Sci. Philadelphia, vol. 12, 



1860, pp. 332-333. 

 Thamnophin angustirostris Ruth\'en, U. S. Nat. Mus. Bull. 61, 1908, pp. 120-124 



(part).— Smith, Zoologica, vol. 27, 1942, pp. 120-121. 



Type.—U.S.'^M. No. 959. 



Type locality. — Parras, Coahuila. 



Range. — Known only from the type locality. 



THAMNOPHIS CHRYSOCEPHALUS (Cope) 



Eutaenia chrysocephalus Cope, Proc. Amer. Philos. Soc, vol. 22, 1884 (1885)^ 



pp. 173-174. 

 Thamnophis chrysocephalus Smith, Zoologica, vol. 27, 1942, p. 104; Proc. U. S. 



Nat. Mus., vol. 93, 1943, pp. 478^79. 

 Thamnophis ehuratus Tayloe, Herpetologica, vol. 1, 1940, pp. 187-189, pi. 19, 



text fig. 2 (tyije locality, Cerro San Felipe, Oaxaca ; type, E. H. Taylor- 



H. M. Smith Coll. No. 556). 



Type.—\J.S:^M. No. 30494. 



Type locality. — Orizaba. 



Range. — Mountains of south-central Veracruz southward through 

 central Oaxaca and westward along the Sierra Madre del Sur, central 

 Guerrero (known from the states of Guerrero, Oaxaca, Puebla, and 

 Veracruz). 



THAMNOPHIS DIGUETI (Mocquard) " 



Tropidonotus Digueti Mooquabd, Nouv. Arch. Mus. Hist. Nat. Paris, ser. 4, vol. 1^ 



1899, pp. 327-329. 

 Thamnophis digueti Fitch, Univ. California Publ. Zool., vol. 44, No. 1, 1940, 



pp. 81-83, pi. 7, fig. 9 (head only). 



Type. — Mus. Hist. Nat. Paris. 



Type locality. — Restricted to San Ignacio, Baja California (in- 

 cluded Mulege, Baja California). 



Range. — Sierra de la Giganta, southern half of Baja California. 



's The type, the only known specimen, probably represents a distinct species, but it may- 

 be a hybrid between ruflpunctatnf! and melanof/aster. 



" We tentatively accept Fitch's arrangement of the various members of tlie ordinoidea 

 group, admitting the existence of contrary views (see Ernst Mayr, Systematica and the 

 origin of species, 1942, pp. 133-134). 



