638 MR. G. A. BOULENGER ON THE 



2. YiPERA. 



Laur. Syn, Hept. p. 99 ; Bouleng. Cat. Sn. iii. p. 471. 



Two species : — 



No supraocular ; anterior nasal separated from tlie rosti"al by a 



naso-rostral , V. Mndii. 



nA. large supraocular; anterior nasal in contact with tlie rostral... V. superciliaris. 



1. ViPERA HINDU Bouleng. Ann, & Mag. IST. H. (8) v. 1910^ 

 p. 513. 



Kenya district. East Africa. 



^ 2. YiPEBA SUPERCILIARIS Peters, Mon. Berl. Ac, 1854, p. 625, 

 and Reise Mossamb. iii. p. 144, pi, xxi. ; Bovileng. Cat, Sn, iii. 

 p. 491, 



German East Africa at Cape Delgado. 



3. BiTis. 

 Gray, Zool, Miscell. p. .69 ; Bouleng. Cat. Sn. iii. p. 492, 



Synopsis of the Species. 



One or two series of scales between the nasal and the rostral ; 



nostrils directed upwards B. arietans: 



4 or 5 series of scales between the nasal and the rostral ; a single 

 enlarged, sometimes horn-like scale above the internasal, in 

 contact with its fellow J3. gahonica. 



4 or 5 series of scales between the nasal and the rostral ; 2 or 3 

 enlarged, horn-like scales above the internasal, usually with 

 small scales between them and their fellows H. nasicorreis, 



1. BiTIS ARIETANS. 



Vipera arietans Merr. Tent, p. 152, 

 Bitis arietans Bouleng. t. c, p, 493. 

 ^ Tropicjvl and South Africa ; Southern Arabia. 



2. Bitis gabonica. 



Echidna gctbonica Dum. & Bibr. Erp. Gen, \\i. p. 1428^ 

 pi. Ixxx. h. 



Bitis gabonica Bouleng. t. c, p. 499. 

 Tropical Africa. 



3. Bitis nasicornis. 



Coluber nasicornis Shaw, Nat, Miscell. iii. pi. xciv. 

 Bitis nasicornis Bouleng. t. c. p, 500, 

 Tropical Africa, 



