118 3. IGUANID3E 



VAN DENBURGH & SLEVIN, Proc. Cal. Acad. Sci., Ser. 4, Vol. XI, 



1921, pp. 28, 31, 40, 42, 51; NELSON, Mem. Nat. Acad. Sci., Vol. 



XVI, 1921, p. 114. 

 Crotafhytus Gambeln BAIRD & GIRARD, Proc. Acad. Nat. Sci. Phila., 



Vol. VI, 1852, p. 126 (type locality, California) ; BAIRD & GIRARD, 



Marcy's Explor. Red River, 1854, p. 205. 

 Crotap&ytus fasciatus HALLOWELL, Proc. Acad. Nat. Sci. Phila., 1852, 



p. 206 (type locality, Jornado del Muerte, New Mexico) ; 



HALLOWELL, Sitgreaves' Exped. Zuni & Colorado Rivers, 1853, 



p. 115, pi. V; HEERMANN, Rept. Pac. R. R. Surv., Vol. X, 1859, 



p. 24. 



Leiosaurus hallowelli DUMERIL, Arch. Mus. Hist. Nat., Vol. VII, p. 533, 

 CrotapAytus cofen YARROW, Proc. U. S. Nat. Mus., 1882, p. 441 (type 



locality, La Paz, Lower California) ; YARROW, Bull. U. S. Nat. 



Mus., No. 24, 1883; p. 53; STEJNEGER, N. Amer. Fauna, No. 3, 



1890, p. 105; VAN DENBURGH, Proc. Cal. Acad. Sci., Ser. 2, Vol. 5, 



1895, p. 93; DICKERSON, Copeia, 1917, No. 50, p. 96; NELSON, 



Mem. Nat. Acad. Sci., Vol. XVI, 1921, pp. 114, 115. 

 Crotapbytus cofii GARMAN, Bull. Essex Inst., Vol. XVI, No. 1, 1884, 



p. 16. 

 Crotapbytus cofei COPE, Bull. U. S. Nat. Mus., No. 32, 1887, p. 45; 



BELDING, West Amer. Scientist, Vol. Ill, No. 24, p. 97. 

 Crotaphytus silus McL-AiN, Critical Notes, 1889, p. 2 (part). 

 Crotap&ytus fasciatus MOCQUARD, Nouv. Arch, du Mus. d'Hist. Nat. 



Paris, Ser. 4, Vol. I, 1899, p. 303, pi. XIII, fig. 1 (type locality, 



Las Palmas, Lower California). 

 Crotafhytus fasciolatus MOCQUARD, Bull. Mus. Hist. Nat. Paris, 1903, 



p. 209 (new name for C. fasciatus). 



Description. Head large, depressed, not so distinct 

 from neck as in C. c. baileyi. Its plates all small, but largest 

 and somewhat convex on snout. Three to five longitudinal 

 rows of shields separating supraocular regions. Nostril 

 large and opening laterally in a round plate much nearer to 

 end of snout than to orbit. Superciliaries small but im- 

 bricate. Rostral plate wide but very low. Supralabials of 

 nearly equal size. A long subocular plate. Ear-opening 

 large, oblique, with very slight anterior denticulation. Supra- 



