256 S A U R I A. 



plate ; they are quite elongated, exteriorly rounded, linear upon their 

 contiguity with the middle occipital, and angular anteriorly, where 

 they come into contact with the supraoculars and the parietals. The 

 temples are protected by scales similar to those of the upper region of 

 the neck, mayhap somewhat larger; the uppermost, lining the latero- 

 occipital, might be termed a shield, from its stronger resemblance 

 to the cephalic plates than to ordinary scales. The supraocular 

 plates are very large, four in number ; the two middle ones trans- 

 versely elongated; the other two, subtriangular. Two very small 

 plates, one at the anterior, the other at the posterior extremity of 

 the supraocular region, might be regarded as supraocular plates also, 

 from the fact of their exhibiting most of their surface in an upper 

 view of the head : still, the anteocular could, with some propriety, be 

 considered as an anteorbital, and the postocular, as a postorbital. Be 

 this as it may, the anterior rim of the eye is formed by two subequal 

 anteorbitals, situated beneath the anteocular just referred to, and the 

 posterior rim, by three of the temporal scales in addition to the postocu- 

 lar. The inferior rim of the orbit is formed by the third, fourth, and 

 fifth upper labials ; the inferior postorbital resting upon the commis- 

 sure between the fifth and sixth labials, and the inferior anteorbital 

 upon a portion of the second upper labial. Two, vertically elongated, 

 rather slender, and subequal lorals may be observed between the ante- 

 orbitals and the nasal plate ; both resting upon the second upper 

 labial, superiorly contiguous : the foremost to the prefrontal, and the 

 hindmost, to the postfrontal. The nasal plate itself is subrhomboid, 

 resting upon the first upper labial, hence, limited anteriorly by the 

 rostral, and superiorly by the prefrontal : the nostril perforates it upon 

 its middle. There are six upper labials, increasing in size posteriorly ; 

 the first and second being quite narrow and elongated ; the rest are 

 deeper, and irregularly angular. The symphyseal is hemidiscoid, and 

 somewhat larger than the rostral ; it is followed, on either side, by four 

 well-developed lower labials, longer than deep, diminishing in size 

 backwards ; one or two exiguous ones may be observed at the angle 

 of the mouth, though not easily distinguished from the adjoining scales. 

 There are five mental shields of considerable development : an ante- 

 rior odd one, followed by two pairs, contiguous upon the middle line 

 of the chin. A small scale may sometimes interpose between the 

 commissure of the posterior pair. A third pair of mental shields 

 might, perhaps, be distinguished from the scales of the throat, in being 



