40. THAMNOPHIS 



Anterior and posterior nasals distinct. One loreal. One pre- 

 ocular and normally three postoculars. Temporals normally 

 one followed by two, sometimes 1 + 1, or 1+3. Seven or rare- 

 ly eight superior and nine or 10 inferior labials j the fifth or 

 sixth superior and fifth, sixth or seventh inferior larg'estj 

 the third and fourth or fourth and fifth superior reaching 

 the eye 5 the first pair of inferior meeting on the median 

 line. Two pairs of genials, the posterior considerably 

 longer than the anterior. Scales on the body in 19 — 19 — 17 

 rows, all keeled, the outer feebly. Anal plate not divided. 

 Gastrosteges varying in number at least from 157 to 168. 

 Urosteges in two series of from 74 to 87. 



The ground color above is olive or olive-brown, vary- 

 ing shades of brown, or blackish brown, usually with more 

 or less red on the sides, chiefly on the skin between the 

 scales, but involving the latter to a greater or less extent 

 in different individuals. There are three longitudinal light 

 lines, one on the middle of the back and one along the sec- 

 ond and third rows of scales of each side. These lateral 

 lines sometimes blend with the light coloration of the belly. 

 Dark brown or blackish spots often are present between the 

 dorsal and lateral lines when the ground color is light 

 enough to cause them to show. The dorsal line usually is 

 bluish, but may be yellow. The belly may be bluish, yel- 

 lowish or grayish white or rarely red. The dorsal stripe 

 averages broader and the belly lighter than in T. sirtalts 

 concsnnus, resembling in these respects T. sirtalis infernalis. 



Length to anus 276 437 489 597 675 678 



Length of tail 90 153 167 178 202 190 



Variation. — In twelve specimens from Utah the loreal 

 is I — 1 in all. The preoculars are 1 — 1 in all. The post- 

 oculars are 3 — 3 in all. The temporals are 1+2 — 1+2 in 

 eight, or 66% j 1+2—1+3 in three, or 25%; and 



