1044 Catalogue of Reptiles inhabiting the [Oct. 



sides of the head. The oval gular scales have a tuhercular appearance. 

 The integuments of the head and body are remarkably lax, like those 

 of Acrochordus javanicus. The neck is covered by 31, the trunk by 

 27 longitudinal series of ovate or conical scales ; they are not imbricate, 

 but are frequently surrounded by the naked skin. The tail is prehensile 

 but less so than in the preceding species. The malayan individuals 

 appear to be less numerous than the Javanese. The four observed 

 were all found on the ground in valleys, The largest, which had been 

 feeding on a rat, was of the following dimensions : 



Length of the head, ft. If inch. 



Ditto ditto trunk, 2 5f 



Ditto ditto tail, 5f 



3 ft. Of inch. 

 Circumference of the neck, 2, of the trunk, 3f , of the root of the tail, 

 1-| inch. 



In general sluggish, but when roused, ferocious habits, the preceding 



three species resemble the genus Bungariis ; their mode of attack is 



also similar: like Vipera russelli, (Shaw)* when it prepares to dart, 



they vibrate the prehensile tail, and utter a faint hissing sound. As the 



pupil is vertically contracted by the light, they frequently miss their 



aim, and like Bungarus, Naja, Vipera russelli and Hydrus, in the 



extreme of fury, they will fix the fangs in their own bodies. Although 



they are averse to motion, they are not of quite so stationary habits as 



represented by M. Schlegel, {Essay : Par tie Descriptive, page 520.) In 



the jungle I have noticed them moving between the branches of trees 



or on the ground, either in search of prey, or after heavy rains have 



flooded their hiding places. In Bengal most terrestrial serpents keep 



the latter during the hot season, but the rains send them abroad in 



search of dry localities. Although the present genus has venomous 



organs, as highly developed as Crotalus or Vipera, the effects produced 



by wounds of two species at least, appear to be less dangerous, than 



might a priori be supposed. According to Russell's experiments with 



the venom of Trigonocephalies gramineus, chickens expired within 8 to 



33 minutes, pigeons in 14 to 18 minutes. A pig recovered in 6 or 



* SvN.-Ilussell, I. PI. 7. Katuka RekulaPoda, II. PL 32.— Coluber russellii, Shaw.— 

 Vipera elegans, Daudin. 



