114 OP HID I A. 



verticis anteriore pdrvo, inter i^ostfrontales sito. Colore sordide flavo 

 sufra, infra vero obsoleto-Jlavo. 



Spec. Char. — Two pairs of frontal plates. An angular loral. Fourth 

 and fifth upper labials entering into the rim of the orbit. A small 

 anterior vertex plate situated between the postfrontals. Uniform 

 isabel-color above, dull-yellow beneath. 



Syn.— Wenona isahella, B. & G. in Proc. Acad. Nat. Sci. Philad. VI, 1852, 176 ; 

 & Catal. N. Amer. Kept. I, 1853, 140. 



Descr. — The eye is larger than in the preceding species, and the 

 snout less protruding. The upper surface of the head is flat; the snout 

 rounded upon its periphery. The normal vertex plate is broader than 

 long and rounded posteriorly. A small plate is situated immediately 

 in advance of the latter and between the postfrontals, which may be 

 considered as a second vertex plate. A small, transversely elongated 

 occipital is observed. There are but two pairs of frontals ; the post- 

 frontals are largest, subangular, united on the right side with the 

 loral, whilst on the left side the loral is distinct from the postfrontal, 

 and angular in shape. The prefrontals are likewise subangular, 

 extending to the first upper labial, and occupying the place of the pre- 

 nasal. The rostral is broad, obtuse-angled above. The anteorbital is 

 large, sub-lozengiform, extending to the upper surface of the head, 

 being produced between the postfrontal and supraoculary, and con- 

 tiguous to the vertex plate. The supraoculary is proportionally larger 

 than in W. plumhea, and irregularly rounded. We observe three sub- 

 angular, polygonal postorbitals ; the middle one being the smallest 

 and elongated. Numerous temporal shields, of the size of the post- 

 orbitals, and slightly smaller than the scales. The cleft of the mouth 

 is nearly horizontal. The upper labials are nine in number ; the 

 anterior five higher, else deeper than the rest ; the fourth and fifth 

 entering into the orbit, and thus replacing the suborbitals which are 

 wanting. There are ten lower labials ; the anterior four larger than 

 the rest. The first pair encloses the symphyseal, and posteriorly 

 along the middle region, may be seen four pairs of mental shields. 



The body is subcylindrical, deeper than broad ; the abdomen being 

 narrow. The tail is short and thick, blunt posteriorly. The scales 

 resemble those of W. plumhea, but are proportionally larger. Those 

 constituting the outer row, not quite so deep compared to their length. 



