40. THAMNOPHIS 795 
181. Thamnophis sirtalis concinnus (Hallowell) 
NorTHWESTERN GARTER SNAKE 
Tropidonotus concinnus HaLLowELt, Proc. Acad. Nat. Sci. Phila., Vol. 
VI, 1852, p. 182 (type locality, Oregon Territory). 
Eutainia pickeringit Barrp & Girarp, Cat. N. Amer. Rept., Pt. 1, Serp., 
1853, p. 27 (type locality, Puget Sound); Grrarp, U.S. Explor. 
Exped., Herp., 1858, p. 150, pl. XIII, figs. 14-20; Lorn, Naturalist 
Vancouver Island, Vol. I, 1866, p. 306 (part). 
Eutainia concinna Bairp & Girarp, Cat. N. Amer. Rept., Pt. 1, Serp., 
1853, p- 146; Lorp, Naturalist Vancouver Island, Vol. II, 1866, 
p- 306. 
Eutenia sirtalis tetratenia Corr, U. S. Explor. Surv. W. 1ooth Merid., 
Vol. V, 1875, p. 546 (part); Cope, Proc. U. S. Nat. Mus., Vol. 
XIV, 1892, p. 664 (Puget Sound, Wash., and Pitt River, Cal.) 
(part); Cope, Report U. S. Nat. Mus., for 1898, 1900, p. 1080 
(part). 
Eutenia sirtalis concinna Corr, Proc. U. S. Nat. Mus., Vol. XIV, 1892, 
p. 664; Cope, Report U. S. Nat. Mus. for 1898, 1900, p. 1081. 
Eutenia sirtalis pickeringii Corr, Proc. U. S. Nat. Mus., Vol. XIV, 
1892, p. 665, Cope, Report U. S. Nat. Mus. for 1898, 1900, p. 
1082; Dirmars, Reptile Book, 1907, p. 238, pl. LX XII, fig. 2. 
Eutenia sirtalis trilineata Core, Proc. U. S. Nat. Mus., Vol. XIV, 1892, 
p. 665, (“Port Townsend, Oregon and Fort Benton, Mont.”) 
(part?); Cope, Report U. S. Nat. Mus. for 1898, 1900, p. 1083 
(part?). 
Thamnophis parietalis pickeringii Van Densurcu, Occas. Papers, Cal. 
Acad. Sci., V, 1897, p. 204. 
Thamnophis sirtalis concinnus RuTHVEN, Bull. U. S. Nat. Mus., No. 61, 
1908, p. 173; STEJNEGER & Barzour, Check List N. Amer. Amph. 
Rept., 1917, p. 103; Van Densurcu & Stevin, Proc. Cal. Acad. 
Sci., Ser. 4, Vol. 8, No. 6, p. 192; SmirH, Copeia, 1920, No. 88, 
p- 102; Van DensurcH & Stevin, Proc. Cal. Acad. Sci., Ser. 4, 
Vol. XI, 1921, pp. 40, 45. 
Thamnophis sirtalis parietalis BLANncHARD, Copeia, 1921, No. 90, p. 6. 
Description—Head distinct from neck, flat topped, with 
narrow, rounded snout. Temporal regions sometimes swol- 
len in old specimens. Eye large. Rostral plate large, bound- 
ed behind by internasal, anterior nasal and first labial plates, 
