906 16. CROTALIDZA 
Crotalus miliarius var. edwardsii Jan, Elenco Sist. degli Ofidi, 1863, 
pe 124: 
Crotalus miliarius JAN, Iconogr. Génér. Ophid., 46e livr., 1874, pl. III, 
fig. 6. 
Caudisona edwardsii Cope, Bull. U. S. Nat. Mus., No. 1, 1875, p. 343 
Yarrow, Surv. W. rooth Merid., Vol. V, 1875, p. 531; YaRRow, 
Bull. U. S. Nat. Mus., No. 24, 1883, p. 78; Cracin, Trans. Kansas 
Acad. Sci., Vol. VII, reprint 1906, p. 118. 
Sistrurus miliarius var. edwardsii GarMAN, Mem. Mus. Compr. Zool., 
Cambr., Vol. VIII, No. 3, 1883, p. 177. 
Crotalophorus catenatus edwardsit Cope, Proc. U. S. Nat. Mus., Vol. 
XIV, 1892, p. 685; Cope, Proc. Acad. Nat. Sci. Phila., 1892, p. 336. 
Sistrurus catenatus edwardsit SrEJNEGER, Report U. S. Nat. Mus. for 
1893, 1895, p. 416, pl. 6; Cope, Report U. S. Nat. Mus. for 1898, 
1900, p. 1144, fig. 328; SreyNEGER, Proc. U. S. Nat. Mus., Vol. 
XXV, 1902, p. 158; Dirmars, Repti'e Book, 1907, p. 438, pl. 
CXXYV, figs. 3, 5; Evtis & Henperson, Univ. Co orado Studies, 
Vol. X, No. 2, 1913, p. 111; STEJNEGER & Barsour, Check List 
N. Amer. Amph. Rept., 1917, p. 107; Vorutes, Univ. Ariz. Agric. 
Exper. Station Bull. No. 83, 1917, p. 364; TERron, Mem. y Rev. 
Soc. Cient. Antonio Alzate, Vol. 39, 1921, p. 180. 
Sistrurus edwardsit, CocKERELL, Amer. Nat., Vol. XXX, 1896, p. 326. 
Sistrurus catenatus BOULENGER, Cat. Snakes Brit. Mus., Vol. III, 1896, 
p- 570 (part). 
Sistrurus catenatus consors Brown, Proc. Acad Nat. Sci. Phila., 1901, 
p- 99; Baitey, N. Amer. Fauna, No. 25, 1905, pp. 28, 49; STRECKER, 
Baylor Bulletin, Vol. XVIII, No. 4, 1915, p. 43. 
Description.—Rather small. Head flat-topped, subellip- 
tical in outline when seen from above. Rostral moderately 
large, bounded behind by internasal, anterior nasal and first 
labial plates. Plates on top of head are a pair of internasals, 
a pair of prefrontals, a frontal, supraocular of each side and 
a pair of parietals. Superior labials 11 or 12, separated from 
eye by one or two scales. Scales on body in 23 or 25 rows, 
strongly keeled except in about two rows on each side. Anal 
plate entire. Gastrosteges varying in number from 136 to 
153. Urosteges in a single series of from 24 to 31. 
The color above is yellowish brown, with three series 
