568 VIPERID, 
i, k-l. Hgr. (Sc. 23; V. Costa Rica. 
157; ©. 49) & yg. (Se. 
eg 4 V. 145, 148; C. 
m. . (Se. 21; V. 188; Chiriqui. J.G. teges 
He [C.]; F. D. Gok. 
man, E 
n. Hgr. (Sc. 23; V. 151; W. Ecuador. Mr, Fraser Cc). 
C. 59). 1 Wh on 
o-p. 2 (Sc. 21; V. 140; Bologna, Ecuador. beadunaies sie 
C. 58) & hgr. (Se. 23; 
V. 140 ; C. 53). 
q, 7-8. 3 '(Se. 19; V. 145; Quito. 
C.?) & 9 (Se. 21, 21; 
V. 144, 148; C. 62, 62). 
39. Lachesis nigroviridis. 
Bothriechis nigroviridis, Peters, Mon. Berl. Ac. 1859, p. 278, pl.—. 
.4; Cope, Journ, Ac. Philad. (2) viii, 1876, p. 150 
oY nigroviridis, F. Mill. Verh. Nat, Ges. Basel, vi. 1878, 
Ate short, rounded, with sharp canthus. Rostral as broad as 
deep or a little broader than deep; nasal entire or semidivided ; 
upper head-scales flat and imbricate, largest and smooth on the 
snout and vertex; 5 to 7 longitudinal series of scales between the 
supraoculars, which are large and sometimes broken up into two; 
internasals small; two postoculars and a subocular, separated from 
the labials by one series of scales; temporal scales obtusely keeled ; 
9 to 11 upper labials, second only exceptionally forming the 
anterior border of the loreal pit. Scales rather feebly keeled, in 19 
rows. Ventrals 134-146; anal entire; subcaudals 49-54, ‘single. 
Tail prehensile. Green or olive above, speckled and spotted with 
black; a black streak on each side of the head, from the canthus 
rostralis, over the outer border of the supraocular shield, to a little 
beyond the angle of the mouth; upper surface of head sometimes 
with black longitudinal streaks; yellowish beneath, some or all of 
the shields black-edged. 
Total length 535 millim. ; tail 90. 
Costa Rica. 
ce. od (V. 142, 134; OC. Rio Frisio, Mr. ey [C.]; 
50, 54) & 9 (V. 141; 0. F, Godman, 
50). Esq. (Py, 
e. d (V. 146; C. 58) & Trazu, F, D. Godman, Esq. 
9 (V. 146; C. 49). (P.}. : 
40, Lachesis aurifer. 
ee aurifer, Salvin, Proc. Zool. Soe, 1860, p. 459, pl. xxxii. 
Bothyicchis aurifer, Cope, Proc. Ac, Philad, 1871, p. 207. 
Bothrops aurifer, F’, Mill. Verh. Nat. Ges. Basel, vi. 1878, p. 401. 
Snout short and broad, with well-marked canthus.  Rostral 
broader than deep; nasal entire or semidivided ; upper head-seales 
