13. COLUBRID.^ 



the western slope of the Cuyamaca Mountains at an altitude 

 of 2,800 feet and in the Upper Sonoran Zone. 



Remarks. — Tantilla e'tsent has more gastrosteges than 

 any other of our species of Tantilla. It differs from T. 

 planiceps and T. zvilcoxi in the position of the white collar. 



Habits. — Almost nothing is known regarding the habits 

 of this snake. One was found by Mr. Frank Stephens in 

 the fireplace of his home at Witch Creek. He says it prob- 

 ably had worked its way up along the brick foundation of 

 the fireplace during the night. 



201. Tantilla nigriceps Kennicott 

 Sonoran Tantilla 



Tantilla tiigriceps Kennicott, Proc. Acad. Nat. Sci. Phila., i860, p. 328 

 (type locality, Fort Bliss, New Mexico, and Indianola to 

 Nueces, Texas); Cope, Bull. U. S. Nat. Mus., No. i, 1875, p. 35; 

 y.-vRROw, Bull. U. S. Nat. Mus. No. 24, 1883, p. 85 (part); Gar- 

 man, Mem. Mus. Compr. Zoo!., Vol. VIII, No. 3, 1883, p. 88; 

 Cope, Proc. U. S. Nat. Mus., Vol. XIV, 1892, p. 598; Cockerell, 

 American Naturalist, Vol. XXX, April, 1896, p. 326; Mc Lain, 

 Critical Notes, 1899, p. 11; Cope, Report U. S. Nat. Mus. for 

 1898, 1900, p. 1 1 13 (part); Brown, Proc. Acad. Nat. Sci. Phila., 

 1901, p. 93; Brown, Proc. Acad. Nat. Sci. Phila., 1903, p. 551; 

 Branson, Kansas Univ. Sci. Bull., Vol. II, No. 13, 1904, p. 414, 

 fig, 23\ Cragin, Trans, Kansas Acad. Sci., Vol. VII, reprint, 1906, 

 p. 118; DiTMARs, Reptile Book, 1907, p. 391; Ellis & Henderson, 

 Univ. Colorado Studies, Vol. X, No. 2, 1913, p. 106, pi. VII, fig. 

 34; Van Denburgh & Slevin, Proc. Cal. Acad. Sci., Ser. 4, Vol. 

 3, 1913, p. 423; Ellis & Henderson, Univ. Colorado Bull., 

 Vol. XV, No. 6, 1 91 5, p. 263. 



Scolecophis fumiceps Cope, Proc. Acad. Nat. Sci. Phila., i860, p. 371. 



Homalocranion planiceps Boulenger, Cat. Snakes Brit. Mus., Vol. Ill, 

 1896, p. 226 (part). 



Tantilla planiceps Stejneger & Barbour, Check List N. Amer. Amph. 

 Kept., 1917, p. 105 (part). 



Description. — Head rounded in outline, very flat above, 



