Venoms: Venomous Animals and Antivenomous Serum-therapeutics. A. Calmette
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; 3 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 subcaudals.
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 supranasals; 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 black marks 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. atropos, 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; 13–14 supralabials; 3 lower labials. Scales on the body in 27–29 rows, all keeled; 126–140 ventrals; 19–26 subcaudals.
Total length, 350 millimetres; tail 30.
Habitat: Cape of Good Hope.
(5) B. cornuta (fig. 38).—Nostrils opening upwards and outwards. Head covered with small, imbricate, strongly keeled scales; 2–5 raised scales, like horns, above each eye; 12–14 scales round the eye; 12–15 supralabials; 2–3 infralabials. Scales on the body keeled, in 25–29 rows; 120–152 ventrals; 18–36 subcaudals.
Colour grey or reddish-brown, with black spots, edged with white and arranged in 3 or 4 longitudinal series; a dark, oblique streak from the eye to the mouth; belly yellow or brown, uniform or spotted.
Total length, 510 millimetres; tail 35.
Fig. 38.—Bitis cornuta. (After Duméril and Bibron.)
Habitat: Cape Colony, Namaqualand, Damaraland.
(6) B. caudalis.—Nostrils opening upwards and outwards. 12–16 scales from one eye to the other across the head; above each eye a single, erect, horn-like scale; 10–16 scales round the eye; 10–13 supralabials; 2–3 infralabials. Scales on the body in 22–29 rows, strongly keeled; 112–153 ventrals; 18–33 subcaudals.
Colour reddish or sandy-grey, with 2 series of brown spots with light centres, and frequently a vertebral series of narrow spots; belly dull yellow, uniform, or with small black spots on the sides.
Total length, 360 millimetres; tail 25.
Habitat: South-west Africa, from Angola to Namaqualand.
(7) B. gabonica (Gaboon Viper, or River Jack Viper).—Nostrils directed upwards and outwards. Head covered with small, moderately keeled scales, smallest on the vertex, 13–16 from eye to eye; 15–19 scales round the eye; a pair of erectile, triangular, nasal “horns,” consisting of sometimes tricuspid shields, between the supranasals; 13–16 supralabials; 4–5 infralabials. Scales on the body in 33–41 rows, strongly keeled; lateral scales slightly oblique; 125–140 ventrals; 17–33 subcaudals.
This viper, which often attains a length of 1,200 millimetres, is brown, with a vertebral series of quadrangular, yellowish, or light brown spots connected by black markings; the belly is dull yellow, with small brown or blackish spots.
Habitat: Tropical Africa (West Africa, from Liberia to Damaraland; Zanzibar, Mozambique).
This species, which is nocturnal, is often met with on the Gaboon, and in the forests near the banks of the Ogowai. Its head is enormous, triangular in shape, and wider above; it has a bulky body, and a very short tail, terminating abruptly in a point.
The Gaboon Viper is a savage snake, with very active venom, and its poison-glands are of the size of large almonds. It lives in virgin forests, among dead wood and rocks. I have several times met with it in manioc plantations on the edge of the woods. In broad daylight it is sluggish, moves somewhat slowly, and never attacks man. It bites only when surprised.
Fig. 39.—Bitis nasicornis. (After Duméril and Bibron.)
(8) B. nasicornis (fig. 39).—Nostrils opening upwards and outwards. Head covered with small strongly keeled scales, smaller on the vertex, 14–16 from one eye to the other; 2 or 3 pairs of compressed, erectile, horn-like shields between the supranasals, usually separated in the middle by 1 or 2 series of small scales; 15–18 supralabials; 4–6 infralabials. Scales on the body in 35–41 rows, strongly keeled; 124–140 ventrals; 16–32 subcaudals.
Colour purple or reddish-brown above, with pale olive or dark brown spots; a vertebral series of brown, black-edged spots, which assume a rhomboidal form; sides of head dark brown, with a triangular light mark in front of the eye, and an oblique light streak from behind the eye to the mouth; belly pale olive, spotted with black or yellow.
Total length, 1,250 millimetres; tail 125.
Habitat: West Africa, from Liberia to the Gaboon.
(d) Cerastes.
Head very distinct from the neck, covered with small juxtaposed or slightly imbricate scales; eyes small, with vertical pupils, separated from the lips by small scales; nostrils opening upwards and outwards. Body cylindrical; scales keeled, with apical pits, in 23–35 rows. Tail short; subcaudals in 2 rows.
(1) C. cornutus (fig. 40).—Snout very short and broad; two erectile horns above the eyes, which are separated by 15–21 scales and surrounded by 14–18; 4–5 series of scales between the eyes and the lips; 12–15 supralabials; 3 infralabials; scales on the body in 27–35 rows; 130–165 ventrals; 25–42 subcaudals.
Fig. 40.—Cerastes cornutus. (After Duméril and Bibron.)
Colour yellowish-brown or grey, with or without brown spots, forming 4–6 regular series, the two middle ones sometimes forming cross-bars; an oblique dark streak behind the eye; belly white; end of tail sometimes black.
Total length, 720 millimetres; tail 90.
Habitat: Northern border of the Sahara, Egypt, Nubia, Arabia, and Southern Palestine.
(2) C. vipera.—Snout very short and broad; head covered with small, tubercularly keeled scales, to the number of 9–13 from eye to eye; no “horns”; 9–14 scales round the eye; nostril between two small shields, separated from their neighbours by 5–6 series of scales; 10–12 supralabials; 3 infralabials. Scales on the body in 23–27 rows; 102–122 ventrals, rather strongly keeled at the sides; 18–26 subcaudals. Colour dull yellow, pale brown or reddish, with or without black spots; end of tail often black above; ventral surface white.
Total length, 340 millimetres; tail 30.
Habitat: