920 16. CROTALID# 
Ser. 2, Vol. 5, 1895, p. 157; Van Densurcu & Stevin, Proc. Cal- 
Acad. Sci., Ser. 4, Vol. 4, 1914, pp. 133, 145; GRINNELL & Camps 
Univ. Cal. Publ. Zool., Vol. 17, No. 10, 1917, p. 196; STEJNEGER 
& Barpour, Check List N. Amer. Amph. Rept., 1917, p. 109; 
STEPHENS, Trans. San Diego Soc. Nat. Hist., Vol. III, No. 4, 1921, 
p. 65; Van Denspurcu & Stevin, Proc. Cal. Acad. Sci., Ser. 4, 
Vol. XI, 1921, pp. 52, 71; Netson, Mem. Nat. Acad. Sci., Vol. 
XVI, 192; peita: 
Crotalus adamanteus ruber Cope, Proc. U. S. Nat. Mus., Vol. XIV, 
1892, p. 690 (type locality, unknown). 
Crotalus atrox ruber STEJNEGER, Report U. S. Nat. Mus. for 1893, 1895, 
p- 439; Brown, Proc. Acad. Nat. Sci. Phila., 1901, p. 104; Drr- 
mars, Reptile Book, 1907, p. 455, pl. CXXCXI, fig. 2; Rirrer, 
Copeia, 1921, No. 94, p. 29. 
Crotalus confiuentus BouLENGER, Cat. Snakes Brit. Mus. Vol. III, 1896, 
p- 576 (part); Mocquarp, Nouv. Arch. Mus. Hist. Nat., Ser. 4, 
Vol. I, 1899, p. 332. 
Crotalus ruber Van Densurcu, Proc. Cal. Acad. Sci., Ser. 2, Vol. 5, 
1895, p. 1007; Van Densurcu, Occas. Papers Cal. Acad. Sci., 
Vol. V, 1897, p. 226; Cope, Report U. S. Nat. Mus. for 1898, 1900, 
p. 1167, fig. 335; Meek, Field Columbian Mus., Zool. Ser., Vol. 
VI, No. 1, 1906, p. 17; Arsatr, Univ. Cal. Publ. Zool., Vol. 12, 
No. 3, 1913, Pp. 44. 
? Crotalus confluentus Mocquarp, Nouv. Arch. Mus. Hist. Nat., Paris, 
Ser. 4, Vol. I, 1899, p. 332. 
? Crotalus confluentus var. atrox Mocquarp, Miss. Sci. au Mexique, 
Pt. III, Rept., 1909, p. 969, pl. 77, figs. 5, 5a. 
Crotalus atrox Townsenb, Bull. Amer. Mus. Nat. Hist., Vol. XX XV, 
1916, p. 426. 
Description.—Large. Head broad, flat-topped, varying 
in outline according to position of fangs, etc. Rostral usually 
higher than wide, in contact with anterior nasal. Two nasals. 
Usually two preoculars, three postoculars, and two to four 
internasals. A large scale just in front of supraocular. Supra- 
ocular large but not raised into a horn-like process; separated 
from its fellow by six or seven irregular rows of scales. 
About 13 to 18 superior and 14 to 19 inferior labials; first 
pair of latter usually divided transversely, in which case the 
