POISONOUS SNAKES OF NORTH AMERICA. 



411 



b". Number of scale rows usually 23 S. c. Edwaidsii 



a?. Prefrontals ill contact with the loreal proper; a whitish stripe from below center 

 of eye to angle of mouth (fig. 46) S. miliarius 



Fig. 45. 

 HEAD OF SISTRURUS CATENATUS. 



From side, showing color pattern. 



Fig. 46. 



HEAD OF SISTRURU* MILIARIUS. 



From side, showing color pattern 



A pretty good character in dubious cases between S. catenatus typi- 

 cal and S. miliarius consists in the pattern of the parietals. if visible. 



Fig. 47. 



rOLOR PATTERN OF TOP OF HEAD OF SISTRURUS 



CATENATUS. 



Fig. 48. 



COLOR PATTERN OF TOP OF HEAT) OF SISTRURUS 



MILIARIUS. 



In the former there is a dark patch covering the center of the parietal 

 8uture (fig. 47), while in the latter the light portion forms a narrow 

 band down the entire length of this suture (fig. 48). 



The Massasauga. 



Sistrunis catenatus,* (Raliuesque). 

 Plate 5. 



ISIS.— Crotalinus catenatus, Ravisesqvk, Amer. Mouthl. Mag., iv, 1818, p. 41. — 

 Crotaliis catenatus, GAR-!dAN, N. Am. Rept., i, Opliid., p. 118 (1883).— <Sis- 

 trurus catenatus, Gakman, N. Am. Rept. i, Ophid., p. 176 (1883).— Joudan, 

 Man. Vert. North. U. S., 5ed., p. 199 (1888). — Taylor, Ann. Rep. Nebraska 

 State Board Agric, 1891, p. 355 (1892).— Osborne, Part. Cat. Anini. Iowa, 

 p. 9 (1892).— H. Garman, Pull. 111. State Lab. Nat. Hist., iii, p. 312 

 (1892).— H. Garman, Bull. Essex Inst., xxvi, 1894, p. 62.— Hay, Batr. 

 Rept. Indiana, p. 126 (1893).— Hurter, Trans. Acad. Sc. St. Louis, vi, p. 

 258 {1S^3). —Crotalophorus catenatus, Cope, Proc. U. S. Nat. Mus.,xiv, 1891, 

 p. 685 (1892).— Hay, Proc. U. S. Nat. Mus., xv, 1892, p. 387. 



JS25.—CrotaIustergeviinus, Say, in Long's Exped. Rocky Mts., i, p. -^99.- Harlan, 

 .Journ. Phila.Acad.,v, 1827, (p, 372).— Harlan, Phys. Med. Res., p. 135, 

 (1835).— DuMERiL ET BiBRON, Erp^t. Gen^r., vii, ii, p, 1479 (1854).— Cope, 

 iu Mitchell's Res. Yen. Rattlesn., p. 125 (1861).— Hayden, Trans. Am. 



From the Latin catenatus, chained, chain-like. 



