(b) Pseudocerastes.
([Fig. 29].)
This genus is represented by a single species (Pseudocerastes persicus), which appears to be exclusively confined to Persia.
The head is very distinct from the neck, and covered with small imbricate scales; the eyes, which are small, have vertical pupils; they are separated from the lips by small scales. The nostrils are directed upwards and outwards. The snout is very short and rounded. The cylindrical body has 23-25 rows of scales; 151-156 ventrals; 43-49 subcaudals.
Fig. 29.—Pseudocerastes persicus.
(After Duméril and Bibron.)
The coloration is gray or brown, with four series of large black spots, and the head exhibits two longitudinal black streaks behind the eyes. The belly is whitish, dotted with black.
Total length, 890 millimetres; tail 110.
(c) Cerastes.
The vipers belonging to this genus are much more common in North Africa, and we shall therefore study them in conjunction with the African snakes. Cerastes cornutus alone, the special habitat of which is Egypt, is sometimes met with in Arabia and on the eastern bank of the Suez Canal.