In striking at its prey or at a man, the Fer-de-lance throws back its head and opens its jaws widely, with the fangs directed forwards. It drives in its poison-teeth as with the blow of a hammer, and quickly draws back again. When very excited, it resumes its position and strikes afresh. It never becomes tame, but is 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.