REPTILES. 217 



SAURIA. 

 FAMILY OF STELLIONIDiE. 



Genus PKOCTOTRETUS, Dum. & B. 



Gen. char. Body rounded or sliglitly depressed, covered wifh imbricated scales ; the upper 

 ones carinated, tlie inferior ones generally smooth ; neither a dorsal nor a caudal crest; head 

 subpyramido-quadrangular, more or less depressed ; cephalic plates moderate, polygonal ; oc- 

 cipital generally not very conspicuous ; teeth on the palate ; sides of neck either folded or smooth ; 

 no subgular fold ; an ear opening ; membrane of tympanum but little depressed ; fingers simple ; 

 tail either long or conical, or moderate and slightly depressed ; no femoral pores ; anal pores ia 

 the males. 



Syn. Froctotretus, Dum. & B. Erp. gen. IV, ISST, 266. 



GuicH. in Gay, Hist, de Chile, Zool. II, 1848, 23. 



PROCTOTEETUS TENUIS, Dum. and B. 

 Plate XL, Figs. 1—4. 



Spec. chab. Cephalic plates usually smooth, occasionally covered with very minute granules . 

 Auricular aperture large ; its anterior margin subtubercular. One series of supralabials. Tem- 

 poral plates irregularly rounded, subimbricated, subtuberculous, and of moderate development. 

 Sides of neck folded and granular. Dorsal scales small, carinated, and posteriorly obtuse ; 

 lateral scales smaller, not imbricated, provided with a rudimentary carina ; abdominal scutellas 

 smooth and mostly entire. Posterior surface of thighs minutely granular. Tail long and 

 slender. Brownish-black, with transverse subcrescentic black bands. 



Syn. Froctotretus tenuis, Dum. & B. Erp. gen. IV, 1837, 279. 



Bell, Zool. of the Beagle, V, Kept. 1843, 7, Plate iii, fig. 2. 

 GuicH. in Gay, Hist. Chile, II, 1848, 32, Erp. Plate i, fig. 1. 

 HoMBK. and Jacq. Voy. au Pole Sud et dans 1' Oceanic, Plate ii, fig. 2. 



Descr. The form, although slender in its general aspect, is less a characteristic of this species 

 than it really is for several others of its congenere. The body is depressed ; swollen upon its 

 middle region ; the limbs being of moderate development. The anterior, when stretched along- 

 side the body, are far from attaining the groins ; and the tip of the longest toe of the posterior, 

 when the latter are brought forwards, reaches the middle region of the neck. The tail is elon- 

 gated, conical, tapering to a point, and nearly twice as long as the body and head together. 



The tongue is large and fleshy ; elongated in shape and depressed, sublanceolated, occupy- 

 ing the entire space between the two branches of the lower jaw. The teeth are of moderate 

 development, smallest anteriorly, and subcylindrical ; whilst posteriorly these are somewhat 

 flattened, or else stouter upon their base. 



The head is depressed, subtriangular in a view from above, and rounded upon the snout. 

 The plates which cover its surface are generally smooth, but exhibit sometimes a very minute 

 granulation, apparent only through a magnifying glass. The cephalic plates vary as regards 

 both their size and number, being smallest when most numerous. In the specimen figured, 

 there are three pairs of frontals : one pair of post-occipitals, an odd occipital, a vertical, and 

 an odd frontal, which are somewhat larger than the rest, and nearly equal among themselves. 

 An inner series of surocularies may be noticed as the next in size ; they are separated from 

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