188 OPHIDIA. 
forest (Salvin), Coban (Sarg) ; Nicaragua, Chontales (Rix), Matagalpa (Lothschuh), 
San Juan (Xantus); Costa Rica (Gabb); Panama (Cope), Chiriqui (Champion).— 
TRopPicaL SourH AMERICA. 
LACHESIS. 
Lachesis, Daudin, Hist. Nat. Rept. v. p. 8349 (1802). 
1. Lachesis mutus. 
Crotalus mutus, Linn. Syst. Nat. i. p. 378. 
Lachesis mutus, Daud. Hist. Nat. Rept. v. p. 351. 
Lachesis stenophrys, Cope, Journ. Ac. N. Se. Phil. viii. p. 152 (1875). 
Hab. Costa Rica, Sipurio (Gabd); Panama (Mus. Brit.).—Tropica, Sout AMERICA. 
BOTHRIECHIS. 
Bothriechis, Peters, MB. Ak. Wiss. Berl. 1859 (March), p. 278. 
Teleuraspis, Cope, Proc. Ac. N. Sc. Phil. 1859 (Dec.), p. 338. 
Thamnocenchris, Salvin, P. Z. 8S. 1860, p. 459. 
Bothriopsis, Peters, MB. Ak. Wiss. Berl. 1861, p. 359. 
Bothriechis, Teleuraspis, Bothriopsis, et Porthidium, Cope, Proc. Ac. N. Sc. Phil. 1871, p. 206. 
The Central-American species may be arranged in the following subgeneric groups :— 
I. Hinder part of the body and tail compressed, prehensile: arboreal 
species. 
A. Upper surface of the head uniformly scaly. 
1. A series of small, more or less erect scales between the superciliary 
scute and the eye. (TELEURASPIS.) . . . . . .. LL 
2. No small scales between the superciliary scute and the eye. 
(BoTHRIECHIS.) 
by 
. schlegeli. 
a. The second labial entering the fossa 2. B. nigroviridis. 
3. B. lateralis. 
b. The second labial not entering the fossa . - ee 4. B. bicolor. 
B. Fore part of the head with scutes above. (THAMNOCENCHRIS.) . 5. B. aurifera. 
II. Hind part of the body and tail non-prehensile : terrestrial species. 
A. Upper surface of the head uniformly scaly. 
1. Snout pointed . 2 2 1 1 ee ee ee ee ee eee 6 Be lansbergii. 
2. Snout obtuse. 
a. Superciliary scute broad. w/w ee eee ee ee Be godmani. 
8. B. ophryomegas. 
6. Superciliary scute narrow. . . woe ww ee YD B. nummifera. 
B. Upper surface of the head partly covered with soutes. (BotHRiopsis.) B. quadriscutata. 
10. B. scutigera. 
