REPTILES OF THE PACIFIC COAST. 201 



Eulcenia sirtalis tetratmnia. Cope, U. S. Explor. Surv. W. 100th 



Mer., V, 1875, p. 546 (no locality); Cope, Proc. U. S. Nat. 



Mns., XIV, 1891, p. 664 (Puget Sound, Wash., and Pitt 



River, Cal.). 

 Eutmnia plckeringii, Cope, Proc. Ac. Nat. Sci. Phila., 1883, p. 21. 

 Tropidonotus sirtalis var. parietalis, Garman, Mem. Mus. Compar. 



Zool., VIII, 3, 1883, pp. 25, 139. 

 Eutcenia sirtalis parietalis. Cope, Proc. U. S. Nat. Mus., XIV, 1891, 



p. 664. 

 Eiitamia sirtalis trilineata, Cope, Proc. U. S. Nat. Mus., XIV, 1891, 



p. 665 (part), (Fort Benton, Mont.). 

 Tropidonotus ordinattis var. iiifernalis, BouLENGER, Cat. Suakes Brit. 



Mus., I, 1893, p. 207 (part). 

 Thamnophis parietalis, Stejneger, N. A. Fauna, No. 7, 1893, p. 214. 



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

 with narrow, rounded snout, and temporal regions some- 

 times swollen. 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 pre- 

 frontals, a frontal, supraocular of each side, and a pair 

 of parietals. Anterior and posterior nasals distinct. 

 One loreal. One preocular and from two to four postocu- 

 lars. Temporals normally one followed by two, some- 

 times 1-1, 1-3, or 2-3. Seven, or rarely eight, superior 

 and nine to eleven inferior labials, fifth or sixth supe- 

 rior and fifth, sixth, or seventh inferior largest, third 

 and fourth or fourth and fifth superior reaching eye, 

 first pair of inferior meeting on median line. Two pair 

 of geneials, posterior longer than anterior. Scales on 

 body in nineteen, or very rarely twenty-one, rows, all 

 keeled except sometimes the first row of each side. 

 Anal plate not divided. Gastrosteges varying in num- 

 ber from one hundred and fifty-one to one hundred and 

 seventy. Urosteges in two series of from seventy-four 

 to ninety-four, a few of the anterior rarely undivided. 

 Eye large. 



There are three light lines, one on the middle of the 



