CROCODILIANS, LIZARDS, AND SNAKES. 



Chionactis occipitalis annulatus Kennuott. 



943 



Catalogue 

 No. 



2105 

 2U495 



22574 



Number 

 of speci- 

 mens. 



Locality. 



When 

 collected. 



Coloraao Desert, Colorado. 

 Chrystoval, Yuma Coun- 

 ty, Arizoua. | 

 Colorado Desert, Colorado. 



I 



From whom received. 



Nature of 

 specimen. 



A. Schott Alcoholic. 



R.J. Young 



C. R. Orcutt 



CHIONACTIS DIASII Cope. 



Chionactis diasii CoPE, Proc. U. S. Nat. Mus., 1886, p. 188. 



Conopsis Uneattis BocoURT, Miss. Sci. Mexique, Reptiles, p. 565, pi. xxv, fig. 4; 



from Tol Ilea lineata Kennicott; uot of Kennicott. 

 Ogmiiis aciitits Cope, Proc. U. S. Nat. Mus., 1886, p. 189.— Boulengek, Cat. Snakes 



Brit. Mus., Ill, 1896, p. 229. 

 Conopsis nasus Guntuer, Cat. Col. Snakes Brit. Mus., 1858, p. 6. 

 Contia nasus Boulenger, part, Cat. Snakes Biit. Mus., II, 1894, p. 268. 



Ceplialic scutes normal ; nostral prominent, not concave above, angu- 

 late viewed in profile; augiilate or rounded from above; as long as the 

 common suture of the prefrontals or prefrontal and iuternasals com- 

 bined. Nostril pierced in front of middle of nasal plate, which is trun- 

 cate posteriorly, joining the square loreal. Oculars, 1-2; temporals, 

 1-2. Frontal oi)enly angulate in front, acutely angnlate posteriorly. 

 Occipitals nearly as wide as long, with regular external and iiosterior 

 borders, not emarginate at median junction. Superior labials seven, 

 all higher than long, third and fourth below orbit. Pregeneials short 

 in contact with only three labials; fourth inferior labial largest and 

 in contact with the very short postgeneial. Gastrosteges, 121-127; 

 urosteges, 32-37. Brown, variously marked above and below with 

 darker; head unicolor. 



. This species embraces two well-marked subspecies, which difter as 

 follows : 



Rostral transversely rounded, its superior surface as long as the common suture of 

 the prefrontals ; color in longi tudinal stripes or series of small spots . C. d. diasii Cope. 



Rostral acute viewed from above; its length equal length of common suture of pre- 

 frontals and internasals; color above in numerous dark cross-bands. 



C. d. acutus Cope. 



CHIONACTIS DIASII DIASII Cope. 



Chionactis diasii Cope, Proc. U. S. Nat. Mus., 1886, p. 188. 



Conopsis lineatus BocouRT, Miss. Sci. Mexique, Reptiles, p. 565, pi. xxv, lig. 4. 



Conopsis nasus Gi-NTHER, Cat. Col. Snakes Brit. Mus., 1858, p. 6. 



Contia nasus Boulengek, part. Cat. Snakes Brit. Mus., II, 1894, p. 268. 



The C. diasii acutus has been found so far only in the Tierra Caliente 

 at Juchitan, at the western i)art of the Isthmus of Tehuan tepee, by 

 F. Sumichrast. 



