140 OPHISAURUS VENTRALIS. 



Hyalinus ventralis, Merrem, Versuch eines Syst. der Ampliib., p. 79. 



Ophisaurus ventralis, Cuvier, Reg. An., torn. ii. p. 69. 



Ophisaurus punctatus, et striatulus, Cuvier, loc. cit., p. 70. 



Ophisaurus ventralis, Wagkr, Naturlich. Syst. der Amphib., p. 159. 



Ophisaurus ventralis, Harlan, Med. and Phys. Res., p. 111. 



Ophisaurus ventralis, Dumeril et Blbron, Hist. Nat. des Rept., torn. v. p. 423. 



Glass Snake, Vulgo. 



Description. The head is sub-oval, elongated, with the snout slightly projecting 

 and rounded, and is covered above with numerous small polygonal plates. The 

 vertical plate is large, elongated, irregularly pentagonal, broader behind, pointed 

 before and surrounded by many smaller plates. There are six large polygonal 

 superior orbital on the outer side, which make an external, slightly projecting 

 superciliary ridge, and this line of plates is continued even to the rostral plate. 

 The frontal is large, irregularly rhomboidal, and surrounded by six smaller plates. 

 There are seven small inferior orbital plates, with many small scales above them, 

 and two small anterior orbital, between which and the nasal are eight or ten small, 

 polygonal, loral plates disposed in three rows. The nasal plate is single and 

 rhomboidal; the rostral is sub-triangular, rounded above and projecting in front. 

 The upper jaw is covered with nine pentagonal, large, labial plates. The nasal 

 plate is simple, small, and quadrilateral. There are eleven superior labial plates 

 on each side, the anterior of Avhich is narrow, rhomboidal, and elevated to touch 

 the plate, separating the rostral and nasal. The third, fourth, fifth, sixth, and 

 sometimes the seventh arc pentagonal and smaller; the eighth, ninth, and tenth 

 are largest of all, and most extensive in the longitudinal direction; the eleventh is 

 smallest. There are sixteen inferior labial plates, that of the chin largest. 



The nostrils are lateral and near the snout, but open upwards and backwards. 



The eyes are rather small, the pupil is black and the iris gre)^ The opening 

 to the external ear is small, oval, and placed behind the angle of the mouth. 



The neck is not contracted, but is of the same size as the head and thora.x. 



