652 13. COLUBRIDZ 
screw, the vermillion urostegial surface outermost. This 
caudal contrivance shown out with conspicuous brilliancy, 
and might have some protective significance as a warning 
mark.” 
142. Diadophis regalis Baird & Girard 
SonorAN RING-NECKED SNAKE 
Diadophis regalis Bairp & G1rarp, Cat. N. Amer. Rept., Pt. I, Serpents, 
1853, p. 115 (type locality, Sonora, Mexico); Bairp, U. S. Mex. 
Bound. Surv., Vol. II, 1859, pl. 22, pl. XIX, fig. 2; Barrp, Rep. 
Pacific R. R. Surv., Vol. X, 1859, pl. XXXIII, fig. 86; Coves, 
Surv. W. tooth Merid., Vol. V, 1875, p. 623; Cope, Bull. U. S. 
Nat. Mus., No.1, 1875, p. 38; Garman, Mem. Mus. Compr. Zool., 
Cambr., Vol. VIII, No. 3, 1883, pp. 73, 159; Yarrow, Bull. U. S. 
Nat. Mus., No. 24, 1883, p. 97; CockreRELL, American Nat- 
uralist, Vol. XXX, April, 1896, p. 326; Cops, Proc. U. S. Nat. Mus., 
Vol. XIV, 1892, p. 615 (part); Wan Densurou, Proc. Cal. Acad. 
Sci., Ser. 2, Vol. 6, 1896, p. 347; Cope, Report U. S. Nat. Mus. 
for 1898, 1900, p. 744 (part); Brown, Proc. Acad. Nat. Sci. Phila., 
Ig0I, p. 70; STEJNEGER, Proc. U. S. Nat. Mus., Vol. XXV, 1902, 
p- 151; Branson, Kansas Univ. Sci. Bull., Vol. II, No. 13, 1904, 
p- 407 (part); Barrey, N. Amer. Fauna, No. 25, 1905, pp. 28, 
35) 45; STRECKER, Proc. Biol. Soc. Washington, Vol. XXI, 1908, 
p- 73; Stone, Proc. Acad. Nat. Sci. Phila., 1911, p. 231; Extis 
& Henperson, Univ. Colorado Studies, Vol. X, No. 2, 1913, p. 
tor, pl. IV, figs. 21, 22; Van DensurcH & Stevin, Proc. Cal. 
Acad. Sci., Ser. 4, Vol. 3, 1913, p. 415; STRECKER, Baylor Bulletin, 
Vol. XVIII, No. 4, 1915, p. 37; STEYNEGER & Barsour, Check 
List N. Amer. Amph. Rept., 1917, p. 76. 
Diadophis pulchellus Yarrow, Surv. W. tooth Merid., Vol. V, 1875, 
p- 538. 
Diadophis punctatus amabilis Yarrow, Bull. U. S. Nat. Mus., No. 24, 
1883, p. 96 (part). 
Diadophis arnyi Yarrow, Bull. U. S. Nat. Mus., No. 24, 1883, p. 96 
(part). 
Diadophis punctatus regalis Cope, Bull. U. S. Nat. Mus., No. 32, 1887, 
p- 80. 
Diadophis regalis regalis Cope, Proc. U. S. Nat. Mus., Vol. XIV, 1892, 
p- 615; Cope, Report U.S. Nat. Mus. for 1898, 1900, p. 744, fig. 155. 
