22. SIAGONODON 62S 



row of small scales runs along the top of the head behind 

 the rostal plate. No supraocular plates are present. The 

 preanal plate is not divided. 



A single species represents this genus in California, Ari- 

 zona and Lower California. 



135. Siagonodon humilis (Baird & Girard) 

 WESTERN WORM-SNAKE 



Rena humilis BAIRD & GIRARD, Cat. N. Amer. Reptiles, Pt. I, Serpents, 

 1853, p. 143 (type locality, Valliecitas, Cal.); COOPER, Proc. 

 Cal. Acad. Sci., Vol. IV, 1870, p. 67; COPE, Bull. U. S. Nat. Mus., 

 No. 32, 1887, p. 64; STEJNEGER, Proc. U. S. Nat. Mus., Vol. XIV, 

 1891, p. 501; COPE, Proc. U. S. Nat. Mus., Vol. XIV, 1892, p. 

 590; STEJNEGER, N. Amer. Fauna, No. 7, 1893, p. 203; VAN DEN- 

 BURGH, Proc. Cal. Acad. Sci., Ser. 2, Vol. 5, 1895, p. 136. 



Stenostoma humile PETERS, Monatsberichte Akad. Wiss. Berlin. i857 

 p. 402; COPE, Proc. Acad. Nat. Sci. Phila., 1861, p. 305; COPE, 

 Proc. Acad. Nat. Sci. Phila., 1886, p. 312; COPE, Bull. U. S. Nat- 

 Mus., No. i, 1875, p. 44; YARROW, Bull. U. S. Nat. Mus., No. 14. 

 1883, p. 142; CARMAN, Mem. Mus. Compr. Zool. Cambr., Vol. 

 VIII, 1883, p. 130; BELDING, West Amer. Scientist, Vol. Ill, No. 

 24, 1887, p. 98. 



Stagonodon dugesii BOCOURT, Miss. Sci. au Mex., Kept., 1882, p. 507, 

 pi. XXIX, fig. 9 (type locality, Colima, Mexico). 



Glaucoma humilis BOULENGER, Cat. Snakes Brit. Mus., Vol. I, 1893, 

 p. 70; COPE, Amer. Naturalist, Vol. XXX, 1897, p. 1014; MOCQUARD, 

 Nouv. Arch. Mus. Hist. Nat., Ser. 4, Vol. I, 1899, p. 315; COPE, 

 Report U. S. Nat. Mus. for 1898, 1900, p. 719, fig. 144; BROWN, 

 Proc. Acad. Nat. Sci. Phila., 1901, p. 14; DITMARS, Reptile Book, 

 1907, p. 210, pi. LXIII. 



Siagonodon humilis VAN DENBURGH, Occas. Papers Cal. Acad. Sci., V, 

 '897, p. 15; McLAiN, Contributions to Neotropical Herpetology, 

 l8 99i P- 3; VAN DENBURGH, Proc. Cal. Acad. Sci., Ser. 4, Vol. 3, 

 1912, p. 153; VAN DENBURGH & SLEVIN, Proc. Cal. Acad. Sci., 

 Ser. 4, Vol. 3, 1913, p. 409; VAN DENBURGH & SLEVIN, Proc. Cal. 

 Acad. Sci., Ser. 4, Vol. 4, 1914, p. 145; STEJNEGER & BARBOUR, 

 Check List N. Amer. Rept., 1917, p. 72; STEPHENS, Copeia, No. 

 J4, 1918, p. 34; VAN DENBURGH & SLEVIN, Proc. Cal. Acad. Sci., 



