57 
HETERODON —Palisot de Beauvais. 
Genus Hetreropon.—Cuaracters. Head large, flat; the rostral plate a trihedral 
pyramid, with a ridge above and pointed at the tip; posterior maxillary teeth 
largest; loral plate single; orbit surrounded with small plates, with the exception 
of the superior orbital. Body and neck distensible. 
.HETERODON SIMUS.—Linneus. 
Plate XV. 
Cuaracters. Head very short, flattened; snout elongated, turned up or slightly 
recurved; azygous plate between the frontal, surrrounded by six or eight smaller 
plates; body grey, with a vertebral series of sub-quadrate or rounded black spots 
or transverse bars; tail fawn colour. PI. 132. Sc. 39. 
Synonymes. Hog Nose Snake, Catesby, Carol., &c., vol. ii. p. 56, pl. lvi. 
Coluber constrictor, Linnzus, Syst. Nat., ed. x. tom. i. p. 216. 
Coluber simus, Linneus, Syst. Nat., ed. xii. tom. i. p. 375. 
La camuse, Lacépede, Hist. des Serp., tom. ii. p. 284. 
Coluber simus, Gmedin, Syst. Nat. Lin., tom. i. pars iii. p. 1086. 
Description. The head is short, flattened and triangular, with the snout 
turned upwards, and rather recurved. ‘The vertical plate is irregularly triangular, 
with its basis broad and turned forward, and its apex directed backwards; there 
is a single, very large quadrilateral superior orbital plate, projecting somewhat 
Vou. LV.—8 
