VIPERA (CERASTES) CAUDALIS. 



colour is quite different, being a steel or ashy grey, with the spots much 

 darker, and tinted with the same hue. The character of the markings upon 

 the head is also subject to great variation, and even sometimes it is entirely 

 different. 



Form, &c— Head distinct from the neck ; body thick in proportion to its 

 length; tail short, tapered, and pointed. The angles of the jaws are very 

 divergent, giving a great width to the hind head ; the anterior portion of the 

 head is much narrower, the nose rounded, and the nostrils situated near its 

 apex, each in the centre of a thick and projecting scale. Eye-brows arched, 

 and each near its middle armed with a slender, pointed, and slightly recurved 

 spine, of about a line or a line and a quarter in length. The scales of the 

 anterior parts of the head, particularly around the eyes, are very small, and 

 those between and immediately behind the nostrils are imperfectly carinated. 

 On the hind-head they are of the same oval form as on the body, and dis- 

 tinctly carinated. On the back and sides they are arranged in longitudinal 

 rows, and from the points of the scales of each row over-lapping the base of 

 the ones immediately behind them, the carina form continuous ridges, generally 

 about twenty-seven in number. The row on each side next to the abdominal 

 plates consists of larger scales of a different shape and without carina. The 

 scales of the tail resemble those of the body, and the two rows coating its 

 under surface, which, in the majority of snakes, are different to those above, 

 are in this species nearly alike, the only difference being, the carince are not 

 so developed. Abdominal plates 149, subcaudal scales 27 pair ; length of 

 adult specimens about 14 inches, of which the tail generally forms nearly the 

 ninth part. 



Dry sandy districts constitute the favourite habitats of this viper, which manifests all that 

 indolence of character so remarkable among the various species of the genus, and on account of 

 which they are more dreaded by the native of South Africa, than even snakes possessed of more 

 virulent poison, but disposed to action on the approach of danger. According to good testi- 

 mony, this species will continue for days together in one position, and as it never seeks to 

 avoid danger, however imminent, its presence is rarely discovered unless when trampled upon, 

 and the offending parts wounded by its fangs. Though generally inactive, it is by no means 

 so when injured ; its movements are then performed with activity ; and when once it seizes the 

 obnoxious object, it retains its hold with great determination, and some considerable exertion 

 is often required to detach it. The same may be said of most of the vipers, in which respect 

 they differ materially from Naia. The various species of the latter, immediately after they 

 inflict a wound, detach themselves, and fly to a place of concealment; while the vipers, even 

 when detached by force, continue upon the spot where they fall, or remove but slowly from it. 



