11. LACHESIS. 5438 
9. Lachesis ammodytoides. 
Bothrops ammodytoides, Leybold, Escurs. Pamp. Argent. p. 80 (1878) ;. 
Berg, An. Soc. Arg. (5) xix. 1885, p. 236; F. Miill. Verh. Nat. 
Ges. Basel, viii. 1887, p. 284. 
Rhinocerophis nasus, Garm. Bull. Mus. Comp. Zool. viii. 1881, p. 85. 
Bothrops nasus, Berg, Act. Ac. Cordoba, v. 1884, p. 96. 
—— patagonicus, J’. Miill. Verh. Nat. Ges. Basel, vii. 1885, p. 697. 
Snout turned up and produced in a low wart, as in Vipera latasti. 
Rostral once and a half as deep as broad; nasal divided; upper 
head-seales small, imbricate, keeled; supraocular large, separated 
from its fellow by 8 or 9 series of scales; two series of scales 
between the eye and the labials; temporal scales keeled; 9 or 10 
upper labials, second separated from the loreal pit, third and fourth 
largest. Scales very strongly keeled, in 23 or 25 rows. Ventrals 
149-160; analentire; subcaudals 30-38 pairs. Pale brown above, 
with large square dark brown black-edged spots or cross-bands 
which may alternate and form a zigzag band; a dark streak behind 
the eye; belly yellowish, dotted with brown. 
Total length 460 millim.; tail 55. 
North-eastern Patagonia and Argentina. 
a. 3 (Sc. 23; V.156; C.37). Rio de Cordoba, E. Fielding, Esq. [P.]. 
Argentina. 
b. @ (Se. 28; V. 149; C.?). 
P Haslar Collection. 
10. Lachesis xanthogrammus. 
Trigonocephalus xanthogrammus, Cope, Proc. Ac. Philad. 1868, 
10 
. 110. 
P Aatheope quadriscutatus, Posada-Arango, Bull. Soc. Zool. France, 
1889, p. 345. 
Head elongate; snout short. Rostral deep; nasal divided ; 
upper head-scales all smooth, in 9 or 10 longitudinal series between 
the large supraoculars ; four elongate shields in a row on the end 
of the snout; 7 upper labials, second forming the anterior border 
of the loreal pit. Scales not strongly keeled, in 27 rows. Ventrals 
196 ; subcaudals 54. Very dark olive above, with a yellow zigzag 
line on each side from the head to the base of the tail, the apices of 
the open A’s usually meeting on the vertebral line, enclosing dorsal 
rhombic spaces and lateral triangles ; top of bead black, with a pair 
of undulating yellow bands from the nape meeting in a A on the 
vertex ; a bright golden band round the end of the snout, involving 
the greater part of the supraocular shields, and extending to the 
nape, bounded below by a black band from the eye to the angle of 
the mouth; labials bright yellow; ventral shields black, paler in 
the middle, with yellow triangular spots at their extremities. 
Total length 1530 millim.; tail 190. 
Pallatanga, EK. Ecuador; Andes of Colombia (?). 
