13. COLUBRID.^ 



brightest just in front of the anus. One specimen had the 

 entire lower surface coral red, becoming grayish or yellow- 

 ish white in alcohol. 



Length to anus 161 162 167 187 188 193 



Length of tail 5 8 5 8 5 7 6+ 63 67 



Distribution. — This species is known only from Lower 

 California, Mexico, where it has been collected in the Cape 

 Region near San Jose del Cabo and in the Sierra de la La- 

 guna. It also has been taken north of the Cape Region near 

 Santa Rosalia and San Ignacio. 



Remarks. — Tantilla 'pla)iiceps resembles T. nigriceps in 

 the number of its gastrosteges, but its nuchal collar is placed 

 farther from the parietal plates. 



Habits. — Mocquard states: "Cet ophidien vit dans le sol, 

 ou on le rencontre surtout en pratiquant des terrassements." 



203. Tantilla wilcoxi Stejneger 

 Arizona Tantilla 



Tantilla nigriceps Cope, Report U. S. Nat. Mus. for 1898, 1900, p. 11 13 

 (part). 



Tantilla coronata Van Denburgh, Proc. Cal. Acad. Sci., Ser. 2, Vol. 6, 

 1896, p. 346. 



Tantilla wilcoxi Stejneger, Proc. U. S. Nat. Mus., Vol. XXV, 1902, 

 p. 156 (type locality, Fort Huachuca, Arizona); Van Denburgh 

 & Slevin, Proc. Cal. Acad. Sci., Ser. 4, Vol. 3, 1913, p. 424; Stej- 

 neger & Barbour, Check List N. Amer. Amph. Rept., 1917, 

 p. 107. 



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

 rather broad across temporal region, but little distinct from 

 neck. Eye moderate. Rostral rather large, broader than 

 high, and bounded behind by internasal, anterior nasal, and 

 first labial plates. Plates on top of head are a pair of small 



