52 RKPTILES. 



Boa cenchrls, L, : Ahoma and Porte Anneau, Daud. ; Seb. I, 1\ i, 

 4, II, xxviii, 2, and xcviii; Boa cenchrya, 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 fossulas 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. Tliese inhabit the East Indies, and may con- 

 stitute a distinct subgenus t. Schneider has separated from the 

 Boas his 



PsEUDO-BOAS SCYTALE, MerV. 



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

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

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

 Erices, or 



Erix§, DaiicL, 



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 



Eupeton|1, Lacep. 



Erpetons, which are very remarkable for two soft prominences covered 

 w-ith 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 broderie (B. Uortulana, L.), Seb. II, Ixxxiv, 1, and the elegaii(, Daud. 

 V, Ixiii, 1, which is the same;— the Bojobi {B. canina, L.), Seb. II, Ixxxi and xcvi, 2, 

 or Xiphusovia araramboja, Spix, VI. The B. hipnale, Seb. II, xxxiv, 1, 2, and Lacep. 

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

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

 made liis genus Coralle, from the probably accidental and mdividual character of 

 tlic two fust plates under the neck being double. 



t 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. 



: Sr,/lale 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 Menem. 



§ Eri.T (hair), a name applied by Linnaeus ta a species of Anguis. 



II From the Greek, Erpetos, Serpent. 



