58 REPTILIA. 



The species known are from America, the most common 

 must be 



Anguis scytale, L. Seb. II, xx, 3. Two feet long, irregularly 

 annulated, white and black.(l) The 



Uropeltis, Cuv. 



Is a new genus allied to Tortrix, in which the tail is still shorter 

 and obliquely truncated above, the truncated surface flat and studded 

 with granules. The head is very small, the muzzle pointed; there 

 is a range of scales along the belly somewhat larger than the others, 

 and a double range of them under their stump of a tail. (2) 



In those non-venomous Serpents, on the contrary, where 

 the mastoid bones are detached, and the jaws are susceptible 

 of great dilatation, the occiput is more or less enlarged, and 

 the tongue forked and very extensible. 



They have long been divided into two principal genera, 

 Boa and Coluber, distinguished by the simple or double 

 plates on the under part of the tail. The genus 



Boa, Lin.(3) 



Formerly comprized all those Serpents, venomous or not, the un- 

 der part of whose body and tail is furnished with uninterrupted, 

 transverse scaly bands, and which have neither spur nor rattle at 

 the end of the tail. As they are rather numerous, even after de- 

 ducting the venomous species, the others have been again subdi- 

 vided. 



. The Boa, properly so called, has a hook on each side of the anus, 

 a compressed body, thickest in the middle, a prehensile tail, and 

 small scales on the head, at least on its posterior portion. It is in this 

 genus that are found the largest serpents on the globe; certain spe- 



(1) Add Jlng. coralUnus, Seb. II, Ixxlii, 2. 1, 3, which is perhaps a mere variety 

 oithescytule; -ing. ater,\d. XXV,'l, and VII, 3; Tortr. rufay Merr., which seems 

 to me a variety of the atra; Ang. maculatus and tessellatus, Seb. II, c. 2; F. latta, 

 N. Seba, II, xxx, 3; Russel, XLIV; Tor^ punctata. Nob., Seb. II, 11, 1, 2, 3, 4, 

 and VI, 1, 4. 



(2) Uropeltis a i/lanicus, Nob. ; Urop. philippinus, two new species similar to the 

 Tortrices even in colour. 



(3) Boa, the name of certain Italian Serpents of great size, most probably the 

 four striped Coluber, or Serpent of Epidaurus of the Latins. Pliny says they 

 were thus named, because they sucked the teats of Cows. The Boa, 120 feet 

 long, which it is pretended was killed in Africa by the army of Reg-ulus, was pro- 

 bably a Python. See Pliny, lib. VIII, cap. xiv. 



