O^t. 12, i38S.] 



SCIENTIFIC NEWS. 



387 



Natural ^i$m&* 



THE PUFF-ADDER. 

 Afbica certainly produces neither rattle-snakes, nor 

 bothrops, nor lance-heads (Trigonocephalus). But she 

 is by no means deficient in venomous serpents. 

 Not to speak of at least one member of the royal 

 house of the death-snakes, Naja haje, she abounds 

 in vipers. The puff-adder (Clotho arictans), a figure of 

 which we borrow from our contemporary La Nature, 

 and which we are about to describe, inhabits all Africa 

 except the portion to the north of the Great Desert, and 

 is especially abundant along the south-western coasts as 

 far as the Cape. Two fine specimens of this species have 



fangs, highly developed, but unequal. They are move- 

 able, conical, curved backwards, but become erect when 

 the serpent opens its mouth. The channel which 

 traverses them gives passage to the venom, and opens at 

 their anterior edge, near the point, by a long slit. These 

 fangs are extremely sharp, and their conical form enables 

 them to penetrate into the tissues without tearing them. 

 As soon as they are withdrawn from the wound, which 

 is a mere prick, the skin, by its elasticity, returns to 

 its place and imprisons the poison which has been in- 

 jected, and which is almost instantly carried by the circu- 

 lation into all parts of the organism. The upper part of 

 the body, including the head, is clad with carinated 

 scales, arranged with much regularity. 



The colour of the puff-adder is very variable. In the 



The Puff- Adder (Clotho Arictans). 



been recently brought from Senegambia, and are living in 

 the reptile-house of the museum at Paris. The body 

 of this serpent is short, thick, and squat, and rarely 

 exceeds four feet in total length. It becomes thinner in 

 the region of the neck, and ends in a triangular head 

 with rounded angles, rather heart-shaped, much broader 

 than the neck, and very flat. The tail is conical and 

 short. Its massive and apparently disproportionate 

 form gives it a hideous aspect. The nostrils, which are 

 wide and have a margin devoid of scales, are very near 

 to each other, and are situated exactly above the muzzle, 

 and not at the sides as in several kindred species of the 

 true vipers. Behind and lying outside the nostrils are 

 the eyes, which are at no great distance, on account of the 

 shortness of the muzzle. 



As in all vipers, the upper jaw is armed on each side 

 and in front with a set of three to five grooved poison- 



specimens now in the museum the prevailing colour is a 

 light brown, verging upon fawn colour. It is relieved 

 on the back by a series of V-shaped marks of a darker 

 colour, opening forwards and generally edged with yellow 

 behind. At the lower part of the sides there is a longi- 

 tudinal range of dark spots, and the top of the head is 

 crossed at the level of the eyes by a brown band, which 

 descends on each side to the margin of the upper lip. 



The puff-adder is excessively slothful, and remains, in 

 general, completely motionless, coiled upon itself, the 

 head resting upon one of its folds. The lower figure in 

 our illustration represents it in this state of repose. Its 

 repugnance to motion is such that it may be almost 

 touched without disturbing itself. It moves only when 

 seeking its food, when attacking or taking to flight, but it 

 then executes rapid movements which contrast with 

 its ordinary sluggishness. Ifmolested, it places itself on 



