VIPERA ATROPOS. 
tail, the former large, flat, heart-shaped, very broad posteriorly, and much 
wider than the neck ; the sides of the head behind the eyes much bulged, 
the head anterior to the eyes narrow, and the latter situated immediately in 
front of the prominent temples ; they are small, deep-seated, and with ver- 
tical pupils. The eyebrows are on a level with the upper surface of the 
head ; opening of each nostril encircled by a slightly prominent ring of a 
horny rough texture, and nearer to the nose than the eye ; rostral plate large, 
triangular, and covers the apex of the nose. Scales about nostrils, and 
between eyes and nostrils, irregular and small, on sides of head behind eyes, 
and over the plates of the upper lip ovate, the former strongly carinated ; 
plates of upper and lower lip eleven, the three anteriormost of the former 
very small. Scales on the anterior portion of the upper surface of the head 
small, subcircular, or ovate, and rather convex or raised, of middle and 
hinder portions oval and strongly carinated. Scales of back and sides ovate 
and carinated, those of the two rows towards the abdominal plates the largest, 
and the keels scarcely visible on the row nearest to the plates. Tail short, 
subcylindrical, slender, and blunt at the point, covered above and on the 
sides with ovate scales strongly carinated, below with two rows of large, six- 
sided, smooth plates. Abdominal plates rather narrow, in many specimens 
double towards the head. Abdominal plates 134 ; subcaudal plates twenty- 
in each row. Length of specimen described, from head to base of tail, 20 
inches; length of tail 2 inches. 
Specimens of this snake have been found in every district of Southern Africa which has 
yet been visited by Europeans. In the colony it is well known to the inhabitants, by whom it 
is designated Berg adder, from the circumstance of its being generally found on the sides of 
hills or upon high grounds. Like the other species of the genus, it is inactive, and rarely bites, 
or attempts to injure men or even animals not suitable for its food, unless assailed, trod on, 
or otherwise excited. Its poison is less virulent than that of other species of the genus, even ot 
smaller size. The specimen described may be considered as having attained rather an unusual 
size — sixteen to eighteen inches may be regarded as a more common length. 
