6 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 



whole under surface is of a whitish colour, sometimes having a slight tint of orange towards the 

 posterior parts, marbled with black. 



Var. C. In this variety the general colour is dark brown, and the yellow or green longitu- 

 dinal lines which characterize the former varieties are but slightly marked ; but the black spots 

 unite and form irregular transverse bands. 



DIMENSIONS. 



Inches. Lines. 



Length of the head 6 



of the body 1 8 



ofthetail 4 6 



7 



This specimen very much resembles in its more tangible characters, the Pr. 

 tenuis ; from which, however, it differs totally in the colouring, and in some mea- 

 sure also in the general form, which is more thick and robust. 



Found in Chile by M. Gay, from whence I also received specimens from Capt. 

 King, and other sources. — " Valparaiso." Mr. Darwin. 



Proctotretus Bibronii. N.S. 



Plate III.— Fig. 1. 



Capite squamis lavibus, subconvexis ; auribus ovalibus, margine anteriore unidentato ; 

 squamis temporum collique rotundatis Icevibus imbricatis ; colli minimis ; serie unicd 

 squamarum supralabialium ; squamis dorsi rhomboideis, carinatis, postice acumina- 

 tis ; abdominis squamis omnibus integris ; femorum facie posteriori omnino 

 granulosa. 



Habitat, Port Desire. Mr. Darwin. 



Description.— General form resembling that of Pr. pictus and cyanogaster. Head moderately 

 short, obtuse, covered with rather large slightly convex scales ; a single row of scales between 

 the labial and the orbitar. The anterior margin of the ear has a single tooth. The temples 

 and the sides of the neck are covered with imbricated scales, which have no carina— those of 

 the neck, especially those on the fold of the skin are smaller and more raised than the others. 

 The scales of the back are rather large, rhomboidal, with a distinct carina, terminating in a 

 point. Those of the abdomen and sides are all of them entire at the margin. The posterior 

 surface of the thighs is wholly granular. 



The only specimen obtained being a female, the number of pre-anal pores is not known. 

 The general colour of this species is brownish grey ; a black longitudinal line runs down 

 the middle of the back and tail. There are two series of black spots on each side, and a 



