466 VIPERID &, 
Aspidelaps, part., Jan, Rev. & Mag. Zool, 1859, p. 510. 
Heterophis, Peters, Mon. Berl. Ac. 1862, p. 276. | 
Dinodipsas, Peters, Sitzb. Ak. Berl. 1882, p. 893; Cope, Proe. Ae. 
Philad. 1883, p. 57. 
Head distinct from neck, covered with symmetrical shields; 
nostril between two nasals and the internasal; loreal present; eye 
moderate, with round pupil, separated from the labials by sub- 
oculars. Body cylindrical; scales smooth or keeled, with apical 
pits, oblique on the sides, in 15-22 rows; ventrals rounded. Tail 
short, subcaudals in two rows or single. 
Tropical and South Africa. 
Skull of Causus rhombeatus. 
Synopsis of the Species. 
I. Scales in 17 rows or more; subcaudals all or greater part in two 
rows. 
Snout obtuse, moderately prominent ; 
scales in 17-21 rows; ventrals 120- 
155 ; subcaudals 15-29 ............ 1. rhombeatus, p. 467. 
Snout prominent, often more or less dis- 
tinctly turned up at the end ; scales in 
19-22 rows; ventrals 134-152; sub- 
caudals 17-25........ Pe PES 2. resimus, p. 468. 
