HALYS HIMALAYANUS. 393 



Halts blomhofpii. 



Trigonocephalus blomhoffii, Boie, Isis, 1826, p. 214-. Schleg. Phys. Serp. ii. p. 552. pi. 20. figs. 8 



& 9, and Faun. Japon. Rept. pi. 6. Gray, Viper. Snakes, p. 14. 

 affinis, Gray, Viper. Snakes, p. 14. 



Snout short, much broader than long, obtusely rounded in front. Frontals well developed, 

 not broken up into smaller shields, but sometimes a smaller piece is detached from the 

 larger shields. Anterior frontals short, transversely produced, and tapering on the sides ; 

 both taken together form a sort of crescent. Seven upper labials, gradually becoming 

 lower behind ; the three posterior are situated below a series of three large temporals ; none 

 of these temporals are in contact with the occipitals, the space between them being filled up 

 with scales. Scales strongly keeled, in twenty-one series. Ventrals 136-150; anal entire; 

 subcaudals 43-56. The tail terminates in a long spine. Brown, mth a series of large, 

 rounded darker spots along each side of the back, the spots of both sides sometimes confluent, 

 sometimes very indistinct ; a series of smaller, irregular brown or black spots along each side 

 of the belly ; belly marbled with brown or blackish. A blackish-brown band runs from the 

 eye along the series of large temporal shields to the angle of the mouth ; it is edged with 

 yellow above and below. All these markings are much more distinct in males and young 

 examples than in old ones ; the former have a curved brown band between the hinder angles 

 of the orbit. 



This species is found in Japan, in the island of Formosa (specimens brought by Consul 

 Swinhoe), and probably in China. A female from Formosa measures 29 inches, the tail 

 being 4y inches. 



Halts himalatanus. (Plate XXIV. figs. A, A'.) 



Trigonocephalus affinis, Giinth. Proc. Zool. Soc. 18G0, p. 167 (not Gray). 



Snout of moderate length, broader than long, with the nose rather protruding. Rostral 

 shield oblique, higher than broad ; frontals well developed, not broken up into smaller 

 shields. The anterior frontals short, transversely produced, and tapering on the sides ; both 

 taken together form a sort of crescent. Posterior frontals large, somewhat pointed in front, 

 and rounded behind. Vertical and supraciliaries as usual in this genus ; occipitals rather 

 small, rounded. Five upper labials, a sixth and seventh being confluent vdth the temporals ; 

 the second is small, not entering the margin of the facial pit ; the third enters the orbit. 

 There is a series of three large temporal shields, the two hinder of which form a portion of 

 the lip ; the space between these temporals and the occipital is covered with small scales. 



Body of moderate length, rounded; its middle is covered with twenty-three series of 

 strongly keeled scales. Ventrals 162-166 ; anal entire ; subcaudals 43-51. The tail termi- 

 nates in a long spine. Dark brown, with large band-like spots across the back ; these spots 

 are very indistinct, scarcely diflering from the ground-colour, and becoming visible only by 

 their black edges ; belly almost entirely black, marbled with yellowish. A broad blackish- 

 brown band runs from the eye along the series of temporal shields to the angle of the mouth ; 



3e 



