6 ZOOLOGY OP 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. 



Van 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 



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 IIL— Fig. ]. 



Capite squainis Iczvihus, suhconvexis ; auribus ovalibus, margine anteriore unidentalo ; 

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

 squamarutn supralabialium ; squamis dorsi rhomboideis, carinatis, postich 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 



