526 VIPERID2Z. 
Closely allied to A. halys, with which it agrees in most respects, 
but snout not turned up at the end, and scales more strongly keeled, 
in 21 (exceptionally 23,—specs. h, s) rows. Upper labials con- 
stantly 7. Ventrals 137-166 ; subcaudals 29-55, Coloration very 
variable. Grey, brown, or red above, with large dark-edged spots 
disposed in pairs, opposite or alternating, or more or less regular 
dark cross-bands; a dark, light-edged temporal band; upper lip 
uniform yellowish or red; belly yellowish or red, more or less pro- 
fusely speckled or spotted with blackish, or nearly entirely black. 
Total length 720 millim.; tail 100. 
Eastern Siberia, Mongolia, China, Japan, Siam. 
a go (V. 140; C. 48). Japan. Leyden Museum. 
b-c. 2 (V. 145; C.47) Yokohama, H.MLS. ‘ Challenger.’ 
& her. d (V. 142; 
C. 55). 
d. 2 (V. 142; C. 48). Okinawa, Loo Choo Mr. M. K. Rokugo 
. Islands. Pt 
e-f,g. d (V.146; C. Tsu Sima, Loo Choo Mr. Holst [C.].. 
46), hgr. (V.138; Islands, 
145; C. 45). | 
an 3 (V. 151,146; Formosa, R.Swinhoe, Esq. [C.]. 
. 40, 46). 
k-n. 2 (V. 142,144; Hoi How, Hainan. J. Neumann, Esq. 
O. ?, 32) & V [P.]. 
o-p. 3 (V. 144,144; Hang-Chau, Prov. Che- J. J. Walker, Esq. 
i P 
©, 41, 35). Kiang. [P:}. 
gq. 2 (V. 140; C. 30). Ichang. A. Henry, Esq. [P.]. 
r. do (V. 143; C. 38). Ichang. R. Swinhoe, Esq,{C. }, 
s. 9 (V. 145; C. 31). Ichang. A. E. Pratt, Esq. [C. }. 
t-u. 2 (V. 142, 188; Mountains N. of Kiu A.E.Pratt, Esq. (CO. 
C. 32, 29). Kiang. 
v-w. 9 (V. 188; C. Mountains N. of Kiu CO. Maries, Esq. [C.]. 
32) & yg. (V. 148; Kiang. 
C. 31). 
z. d (V. 187; 0.46). ——P Sir E. Belcher [P.]. 
(Type of 7. affinis.) 
8. Ancistrodon himalayanus. 
Halys himalayanus, Giinth. Rept. Brit. Ind. p. 398, pl. xxiv. fig. A 
(1864) ; Steindachn. Novara, Rept. p. 87 (1867) ; Stoliczka, Journ. 
As. Soc. Beng. xxxix. 1870, p, 226; Anders. Proc. Zool. Soc. 
1871, p. 196, and 1872, p. 401; Fayrer, Thanatoph. Ind. yl. xvi. 
(1874); Theob, Cat. Rept. Brit. Ind. p. 225 (1876); Blanf. Zool. 
2nd Yark. Miss., Rept. p. 24 (1878). 
Trigonocephalus himalayanus, Strauch, Schl. Russ, R. p. 234 (1878). 
sya). offii (non Boie), Jan, Icon, Gén, 46, pl. y. figs. 4 & 5 
sr himalayanus, Bouleng. Faun. Ind., Rept. p. 424, fig. 
). 
Snout hardly turned up, with sharp canthus. Rostral as deep 
as broad, or a little broader than deep; a pair of internasals 
