652 13. COLUBRIDJE 



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 BAIRD & GIRARD, Cat. N. Amer. Rept., Pt. I, Serpents, 

 1853, p. 115 (type locality, Sonora, Mexico); BAIRD, U. S. Mex. 

 Bound. Surv., Vol. II, 1859, pi. 22, pi. XIX, fig. 2; BAIRD, Rep. 

 Pacific R. R. Surv., Vol. X, 1859, pi. XXXIII, fig. 86; COUES, 

 Surv. W. looth Merid., Vol. V, 1875, p. 623; COPE, Bull. U. S. 

 Nat. Mus., No.i, 1875, p. 38; CARMAN, Mem. Mus. Compr. Zool., 

 Cambr., Vol. VIII, No. 3, 1883, pp. 73, 159; YARROW, Bull. U. S. 

 Nat. Mus., No. 24-, 1883, p. 97; COCKERELL, American Nat- 

 uralist, Vol. XXX, April, 1896, p. 326; COPE, Proc. U. S. Nat. Mus., 

 Vol. XIV, 1892, p. 615 (part); VAN DENBURGH, 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., 

 1901, 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); BAILEY, 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; ELLIS 

 & HENDERSON, Univ. Colorado Studies, Vol. X, No. 2, 1913, p. 

 101, pi. IV, figs. 21, 22; VAN DENBURGH & SLEVIN, Proc. Cal. 

 Acad. Sci., Ser. 4, Vol. 3, 1913, p. 415; STRECKER, Baylor Bulletin, 

 Vol. XVIII, No. 4, 1915, p. 37; STEJNEGER & BARBOUR, Check 

 List N. Amer. Amph. Rept., 1917, p. 76. 



Diadophis pulchcllus YARROW, Surv. W. iooth 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. 



