72 VENOMS 



spring high enough to strike a rider on horseback. It feeds upon 

 rats and mice, in search of which it often approaches habitations. 



The Hottentots hunt it in order to obtain its venom; they 

 pound its head between stones, and mix the pulp with the juice 

 of certain plants for the purpose of poisoning their arrows. 



It lives for a fairly long time in captivity. At the Pasteur 

 Institute at Lille I have succeeded in keeping one of these snakes 

 for two years, feeding it by forcing milk and eggs down its throat. 



(2) B. peringueyi. — Nostrils opening upwards and outwards. 

 Head covered with small, strongly keeled scales, which are smallest 

 on the vertex; 11 scales round the eye; 8 series of scales between 

 the eye and the lip; 11 — 14 supralabials. Scales on the body 

 in 25—27 rows, strongly keeled ; 130—132 ventrals ; 19—28 sub- 

 caudals. 



Colour greyish-olive, with 3 longitudinal series of grey or 

 blackish spots ; head sometimes with a trident-shaped dark mark, 

 followed by a cross ; under surface whitish, with small dark spots. 



Total length, 325 millimetres ; tail 26. 



Habitat: Angola and Damaraland. 



(3) B. atropos. — -Nostrils opening upwards and outwards, 13 — 16 

 scales round the eye ; 2 — 5 series of scales between the supra- 

 nasals ; 10 — 12 supralabials ; 3 — 4 infralabials. Scales on the body 

 in 29—31 rows, all strongly keeled ; 124—145 ventrals ; 18—29 

 subcaudals. 



Colour brown or grey-brown, with 4 longitudinal series of dark 

 spots, edged with black and white ; two large l)lack mai'ks on the 

 head ; belly grey or brown, with darker spots. 



Total length, 350 millimetres ; tail 25. 



Habitat: Cape of Good Hope. 



(4) B. inornata. — Eyes smaller than in B. atropios, and separated 

 from the lips by 4 series of scales ; supraorbital region raised, 

 but without erect horn-like scales ; 15 — 17 scales across the head ; 

 18 — 14 supralabials ; 3 lower labials. Scales on the body in 27 — 29 

 rows, all keeled ; 126 — 140 ventrals ; 19 — 26 subcaudals. 



