340 PROCEEDINGS OF THE ACADEMY OF 



B. v i r i d i s connects the South America and East Indian species insepar- 

 ably ; and to ns it appears questionable whether B. sumatranus and 

 Hombronii are generically distinct. 



Cryftelytrops nobis. 



Head very distinct, depressed anteriorly, covered with small smooth scales. 

 Superciliary region covered with small scales, not thickened as in 'Atropos. 

 Superciliary plate narrow, rudimentary, resting on the preoculars. Pupil 

 elliptical. Urosteges two-rowed. 



24. C. c arin at u s nob. Trimesurus carinatusGray, Zoological Miscellany, 

 p. 48. 



One spec. Hab. ? (Probably India) ? 



To Dr. Gray's very brief description we add the following : Body rather 

 slender, tail moderate. Scales in 25 longitudinal rows, lanceolate, strongly 

 carinate, except a row on each side adjacent to the scuta. Temporals small, 

 keeled. Superior labials small posteriorly, the third largest ; eye over the 

 fourth and fifth, from which it is separated by three rows of scales. Gastro- 

 steges 157. One entire anal. 77 Urosteges. Above, dark olive brown ; beneath 

 blackish green; a greenish white oval apical spot upon each scale of the 

 smooth series next the scuta on each side. 



Trimesurus albolabris Gray, loc. cit., may be a second species of ibis 

 genus, which intervenes between Bothrops and Atropos. 



Atropos Wagler. 

 Nat. Syst. der Amphib. p. 175. 



25. A. D a r w i n i D. & B. Two spec. Hab. ? Dr. Wilson. 

 In this very vicious looking species all the scales are smooth except a few 



dorsal rows. No. 100 ; gastrosteges 165 ; anal 1, entire ; urosteges 51. No. 101 : 

 163x1^53. Prof. Jan (Rev. et Mag. Zoologie, 1859, p. 157,) has described a 

 third Atropos, which has a long horn-like appendage over each eye. This 

 peculiarity, formerly known only in the Cerastes and Clothos of the old world, 

 characterizes three species of American Crotalidse, viz : Crotalus cerastes 

 Hallow, Atropos u n d u 1 a t u s Jan, and Teleiiraspis Schlegeli nob. 



2. VIPERINJZ. 



Cerastes Wagler. 

 L. c. p. 178. 



25. C. Hasselquistii Gray, Zool. Misc. 1832. Coluber cerastes L. Syst. 

 Nat. 1766. Cerastes cegyptiacus D. & B. vii. p. 1440, 1854.* 



Two spec. North Africa, Dr. Wilson. 



Clotho Wagler. 



Gray Zool. Misc. 69, 1842. Echidna et Cerastes pars Wagler, Amphib. 177, 

 '78, 1830. t Echidna Dura, and Bibr. (not of Merrem,) vii. 1420, 1854. 



27. C. rhino c ero s . Cerastes nasicornis Hallow. Proc. Acad. Nat. Sci. 

 Phila. iii. p. 319. Vipera rhinoceros Schlegel, Verslageh en mededeelingen der 

 Koniglijke Akadamie von Wettenshappen ; Amsterdam, iii. p. 316. 



Three spec. Gaboon, Dr. Henry A. Ford. 



In No. 154 (large specimen), there is on the muzzle, below and in front of each 

 horn-like supranasal, an oval scale, directed outward and upward, and free for 

 the greater part of its length. In No. 155, (still larger specimen,) this scale is 

 produced into a horn, four lines in length. The scales of the head are more 

 strongly carinate and spinous in this than in' the last. InC. nasicornis 

 Gray, the horns are all developed from the supranasal plate, which is the 

 character by which Schlegel distinguishes it. 



* Aspis Cleopatrae Laurenti, Specimen p. 105, cannot be this species. He says, ' sguanjj* 

 planis appressis nee carinatis." 



[Dec. 



