324 S A U R I A. 



the latter being composed of very small plates, situated between the 

 supraciliary ridge and the curvilinear series, the inner of which is 

 composed of the largest plates of that region. A series of four or five 

 flattened scales may be observed above the posterior portion of the 

 supraciliary ridge, which extends conspicuously as far as the nostril. 

 The supraciliary ridge itself is composed of five thin and elongated 

 plates, and two or three short ones above the posterior rim of the 

 orbit. Its continuation along the face takes place through the means 

 of two very convex plates. The nostril is situated just above this 

 ridge, perforating a small oblong plate, separated from the rostral by a 

 narrow prenasal and the first supralabials. The suborbital plate is 

 quite developed, narrowest upon its middle, and dilated at both extre- 

 mities. An anteorbital of moderate development closes the suborbi- 

 tal chain by coming into contact with the supraciliary ridge. There 

 are but two loral plates, the anterior being the smallest, and contiguous 

 to the nasal. Four narrow and elongated plates constitute a series of 

 supralabials, extending from the nasal to a small distance beyond the 

 middle of the eye. The rostral is low, convex above, and transversely 

 elongated. There are six upper labial plates on either side, elongated 

 and narrow, somewhat broader, however, than the supralabials, and in- 

 creasing in length from the anterior one to the fourth, then abruptly 

 decreasing. The symphyseal is quite conspicuous and subelliptical ; 

 the lower labials, five on either side, are larger also than the upper: the 

 second, third, and fourth are subequal, the first and fifth being some- 

 what smaller. Three pairs of rather large mental shields may be seen 

 diverging from the symphyseal ; the remaining pairs are scarcely dis- 

 tinguishable from the scales at the angle of the mouth, one series of 

 which extending forwards, between the lower labials and the mental 

 shields, a little beyond the posterior edge of the first labial and first 

 mental shield, though not reaching the symphyseal. The scales under 

 the head are smooth, subequal, subrhorabic, increasing in size towards 

 the chest, where they are largest. The temporal region is protected 

 by small, scale-like, keeled plates. The auricular aperture is propor- 

 tionally large, provided, upon its infero-anterior edge, with two pro- 

 jecting scales. The tympanum is somewhat sunk, though still visible. 

 The neck is but slightly contracted, and exhibits sideways a sub- 

 horizontal and conspicuous fold, under which is a small pouch; 

 another, much smaller fold, may be observed immediately in advance 

 of the shoulder. The scales are small, elongated, or sublanceolated, 



