552 



VIPERID^. 



being constant; belly yellow, more or less profusely spotted or 

 marbled with black. 



Total length 930 millim. ; tail 145. 



Ehasi hills, Assam ; Tibet ; Upper Yang-Tse-Kiang. 



a^c. S (Sc. 21, 21 ; V. 175, 

 173 ; 0. 56, 58) & $ 

 (Sc. 23 ; V. 164 ; C. F). 



d. $ (Sc. 21 ; V. 175 ; C. 54). 



e-4. S (So. 22, 21; V. 183, 

 180; 0. 67, 63) & ? 

 (Sc. 21, 21, 21; V. 186, 

 187, 185 ; 0. 58, 60, 65). 



h. 6 (Sc. 21 ; V. 188 ; 0. 54). 



Khasi hills. 



Khasi hills. 

 Ichang. 



T. C. Jerdon, Esq. [P.]. 

 (Type.) 



Col. Beddome [0.]. 

 A. E. Pratt, Esq. [P.]. 

 (Types of T. xanthomelas.) 



Kia-tiang-fu, 

 Prov. Sze- 



A. E. Pratt, Esq. [C.]. 



Chuen, 1070 ft. 



22. Lachesis mucrosquamatus. 



Trigonocephalus mucrosquamatus. Cantor, Proc. Zool. Soc. 1839, 



p. 32. 

 Craspedocephalus elegans, Gray, Cat. p. 7 (1849). 

 Trimeresurus mucrosquamatus, Cfiinth. Kept. Brit. Ind. p. 390 (1864) ; 



Swinhoe, Proc. Zool. Soc. 1870, p. 411, pi. xxxi. ; Theob. Cat. Sept. 



Brit. Ind. p. 224 (1876) ; Fischer, Jahrb. Hamb. Wiss. Anst. v. 



1888, p. 21 ; Boulenff. Faun. Ind., Rept. p. 428 (1890). 



Bostral slightly broader than deep ; nasal divided or semidivided ; 

 upper head-scales extremely small, granular, smooth or obtusely 

 keeled ; supraocular large, or rather narrow ; 2 or 3 scales sepa- 

 rating the internasals in front ; 10 to 15 scales on a line between 

 the supraoculars ; three to five minute postoculars and a subocular, 

 which is separated from the labials by one, two, or three series of 

 scales ; temporal scales smooth ; 7 to 11 upper labials, second form- 

 ing the anterior border of the loreal pit. Scales strongly keeled, in 

 25 or 27 rows. Ventrals 183-218 ; anal entire ; subcaudals 72-92 

 pairs. Brownish grey above, with a dorsal series of large blackish 

 spots and a lateral series of smaller ones ; a blackish streak from 

 the eye to the angle of the mouth ; lower parts brownish, spotted 

 with white. 



Total length 1050 millim. ; tail 210. 



Formosa ; Naga hills, Assam. 



a. S (Sc. 25; V. 200 



0. 92). 

 h. $ (Sc. 27 ; V. 214 



0. 76). 



c. Yg. (Sc. 27; V. 211 

 0. 89). 



d. Yg. (Sc. 27 ; V. 210 

 C. 90). 



e,f. c? (Sc. 25; V. 187 

 0. 76) & yg. (Sc. 25 

 V. 183; 0.72). 



Takow, Formosa. R. Swinhoe, Esq. [0.].' 

 Formosa. R. Swinhoe, Esq. [0.]. 

 0. Formosa. Mr. Hoist [0.]. 

 S. Formosa. Dr. J. G. Fischer. 

 ? Sir E. Belcher [P.]. 



