114 VENOMS 
hammer, and quickly draws back again. When very excited, it 
resumes its position and strikes afrésh. It never becomes tame, 
but 1s capable of living a fairly long time in captivity. I have kept 
a number of specimens of it for more than two years, caged in my 
laboratory. 
(3) L. atrox (Labaria).—Closely resembling L. lanceolatus, 
but bulkier; the enormous head is armed with powerful fangs, 
which are often more than a centimetre in length; 7 supralabial 
shields ; scales in 25—29 rows, strongly keeled ; 161—216 ventrals ; 
47—73 pairs of subcaudals. 
Colour brown, with dark cross-bands or triangular blotches, with 
the apices adjacent on the vertebral line; a dark streak from the 
eye to the angle of the mouth ; belly yellowish-white, speckled with 
brown, or brown spotted with yellowish-white. 
Total length, 1,110 millimetres; tail 180. 
Habitat: from Central America to Peru and Northern Brazil. 
(4) L. pulcher—Two postocular shields and a subocular, 
separated from the labials by one series of scales: 7 supralabials ; 
scales in 21 or 23 rows, strongly and tubercularly keeled : 156—172 
ventrals ; 58—64 pairs of subcaudals. 
Colour olive-grey, with brown, light-edged cross-bands, which 
are continuous or broken on the vertebral line; a light streak 
from the eye to the angle of the mouth; belly covered with minute 
confluent brown markings, with darker and lighter spots on the 
sides. 
Total length, 685 millimetres; tail 115. 
Habitat: Andes of Ecuador. 
(5) L.microphthalmus.—Snout short, rounded ; eyes very small ; 
7 supralabials, of which the third and the sixth or seventh are 
the largest; scales in 23 rows, dorsals tubercularly keeled ; 159— 
161 ventrals ; 52—55 subcaudal pairs. 
Colour yellowish-brown or pale olive on the back, with dark 
brown triangles on the sides; posteriorly, the united triangles 
form cross-bands ; a yellowish band from the eye to the side of 
the neck ; belly dark brown with yellowish spots. 
