THE POISONOUS SNAKES OF INDIA. 



319 



Lachesis mucrosquamatus — The Formosan Viper. 



Identification. - The scales in the posterior part of the body number 

 21 or 19, the nasal not united to 

 the 1st labial, and the presence 

 of a subocular establish the 

 diagnosis, but all three characters 

 must co-exist. 



Supplementary characters : In- 

 ter nasals. — A pair separated by 

 from 2 to 4 small scales. 

 Supraocular — A single shield. 

 JSasal — Not united with the 1st 

 labial, one or more minute scales 

 intercalated between it and the 

 2nd labial. Subocular not touch- 

 ing the 3rd labial. 2nd labial 

 with a furrow in its upper part 



Jh* 



Fig. 31. — Lach' sis mucrosquamatus 

 (nat. sizo). 



directed into the loreal pit. Scales. — Anterior, 25 to 27; midbody,-23 

 to 27 ; posterior, 19 to 21. 



Distribution. — Saga Hills and Assam, also Formosa. 



Poison. — Nothing known. 



Dimensions. — Grows to 3^ feet. 



Colour. — Brownish with 3 longitudinal series of blackish spbts,»the 

 vertebral series being the largest. Belly mottled brownish and white, or 

 uniform whitish. 



Lachesis jerdonii- 



Fi-j. 32.— LacliesiR jerdonii (nat. Bize - ). 



Jerdon's Viper. 



Identification. — The subocular 

 touching the 3rd labial together 

 with 7 to 8 supralabials mako 

 diagnosis certain. 



Supplementary characters : 

 Internasals, — A pair, separated 

 by from 1 to 3 small scales. 

 Supraocular — A single shield 

 preceded by an enlarged shield 

 peculiar to this species. Nasal 

 not united with 1st labial; 

 small scales may or may not be 

 intercalated between it and the 



