830 13. COLVBRID^T 



Cal. Publ. Zool., Vol. 17, No. 10, 1917, p. 180 (part); Stejneger 

 & Barbour, Check List N. Amer. Amph. Rept., 1917, p. 102 (part); 

 Blanchard, Copeia, 1921, No. 90, p. 6. 



Thamnophis elegans Cockerell, Univ. Colorado Studies, Vol. VII, No. 

 1, 1910, p. 131; Ellis & Henderson, Univ. Colorado Studies, 

 Vol. X, No. 2, 1913, p. 88; Ellis & Henderson, Univ. Colorado 

 Bui!., Vol. XV, No. 6, 1915, p. 261; Dice, Univ. Cal. Pubis. Zool., 

 Vol. 16, No. 17, 1916, pp. 303, 304, 310, 319, 321. 



Thamnophis ordinoides vagrans Van Denburgh & Slevin, Proc. Cal. 

 Acad. Sci., Ser. 4, Vol. VIII, No. 6, 1918, p. 240, pi. 10; Van Den- 

 BURGH & Slevin, Proc. Cal. Acad. Sci., Ser. 4, Vol. XI, 1921, pp. 

 29, 37, 40, 46, 52- 



Description. — Head distinct from neck, flat-topped, 

 with narrow rounded snout. Temporal regions sometimes 

 swollen in old specimens. Eye moderate. Rostral plate 

 large, bounded behind by internasal, anterior nasal, and first 

 labial plates. Plates on top of head: A pair of internasals, 

 a pair of prefrontals, a frontal, supraocular of each side, 

 and a pair of parietals. Anterior and posterior nasals dis- 

 tinct. One loreal. One preocular, rarely two or three. 

 Postoculars normally three, rarely two or four. Temporals 

 normally one followed by two, sometimes 1+3. Eight, 

 or rarely seven, superior and eight to eleven, normally ten, 

 inferior labials, usually the fifth, sixth or seventh superior, 

 and fifth, sixth or seventh inferior largest, the fourth and 

 fifth or third and fourth superior reaching eye, the first 

 pair of inferior meeting on the median line. Two pairs of 

 genials, the posterior equal to or shorter than anterior. 

 Scales in 21 or very rarely 19 rows, all keeled except some- 

 times, the first row on each side. Anal plate not divided. 

 Gastrosteges varying in number from 14-8 to 182, males 

 having 159 to 182, females from 148 to 177. Urosteges 

 in two series of from 67 to 95, males having from 79 to 95, 

 females from 61 to 83. 



