52 REPTILES. 



Boa cenchris, L. : Aboma and Porte Anncau, Daiid. ; Seb. I, Ivi, 

 4, II, xxviii, 2, and xcviii; Boa ccnchrya, Pr. Max. liv. VI. 

 Fawn-coloured, with a suite of large brown rings along the back, and 

 variable spots on the flanks. 



These three species, which attain a nearly equal size, inhabit the 

 marshy grounds of the hot parts of America; attaching themselves 

 by their tail round some aquatic tree, they dart their floating body 

 upon the quadrupeds which come there to drink. 



4. Some have plates on the muzzle, the side of the jaw being 

 grooved so as to resemble a slit beneath the eye, and further back*. 



5. Finally, there are others in which the fossula? are wanting, but 

 whose muzzle is furnished with slightly prominent plates, cut 

 obliquely from behind forwards, and truncated at the end, so that 

 they terminate in a wedge. Their body is greatly compressed, and 

 their back carinated. These inhabit the East Indies, and may con- 

 stitute a distinct subgenus)". Schneider has separated from the 

 Boas his 



Pseudo-boas — Scytale, Merr. 



Which have plates like the Coluber, not only on the muzzle, but also on 

 the cranium; no fossulse, a round body, and the head and trunk one uni- 

 form piece, as in TortrixJ. Daudin also has separated it from the 

 Erices, or 



Erix§, Baud., 



"Which differ from the Pseudo-boas in their tail being very short and ob- 

 tuse, and in the ventral scales being narrower. Their head is short, and 

 nearly of one uniform piece with the body; these characters would ap- 

 proximate them to Tortrix if the conformation of their jaws did not forbid 

 it; besides, the head is only covered with small scales. There is no hook 

 near the anus. We may approximate to these the 



Ekpeton||, Lacep. 



Erpetons, which are very remarkable for two soft prominences covered 

 with scales borne by them on the end of the muzzle. The head is fur- 

 nished with large plates, those on the belly have but little breadth, and the 



* The Boa brodcrie (B. hortulana, L.), Seb. II, lxxxiv, 1, and the elegant, Daud. 

 V, Ixiii, 1, which is the same;— the Bojobi (B. ca?iina,L.), Seb. II, Ixxxiand xevi, 2, 

 or Xiphosoma araramboja, Spix, VI. The B. hipnalc, Seb. II, xxxiv, 1, 2, and Lacep. 

 II, xvi, 11, appears to be nothing more than a young Bojobi; — the B. Merremmii, 

 Sch.il., Merr. Beytr. II, ii, or Xiphosoma dorsuale, Spix, XV, of which Daud. has 

 made his genus Coralle, from the probably accidental and individual character of 

 the two first plates under the neck being double. 



f The B. carinata, Schn., or the ocellata, Opp.; — the B. viperina, Sh. Russel, pi. 

 iv- — N. B. These two subdivisions form the genus Xiphosoma, Fitz., the Cenchris 

 of Gray. 



% Sai/tale coronata, Merr. Seb. II, xli, 1, Pr. M. liv. VII. N. B. The Scytale of 

 Merrem must not be confounded with that of Daudin, which is the Echis of Merrem. 



§ Erix (hair), a name applied by Linnseus to a species of Anguis. 



|| From the Greek, Erpetos, Serpent. 



