8 ARKIV FÖR ZOOLOGI. BAND 9. NIO 3. 



collar; the collarplates ten, rather elongate (twelve, if a 

 lateral pair of scale-like plates is counted in). 



Dorsal scales quadrangular, striated and keeled, once and 

 a half as long as broad, nuchal soales smooth, rounded, in 

 several series; forty-two transverse rows from occiput to base 

 of tail; the rows interrupted on the median line by small 

 scattered scales irregularly arranged. Behind the shoulder 

 and in front of the groin the sides are covered with small 

 oval scales, but on the middle of the sides the scajes are 

 similar to those of the back, the regular transverse rows 

 continuing nearly to the ventrals from which they are sepa- 

 rated only by a narrov strip of about two rows of small 

 scales. Ventrals large, quadrangular, smooth, in twelve longi- 

 tudinal rows (the outermost very small) and in twenty-three 

 transverse ones; thirty-eight scales in all round the body. 

 Prseanals eight, an anterior pair and a posterior row of six 

 plates, the outermost being rather small. Scales of limbs 

 smooth; scales of the tail like those of the body. Femoral 

 pores seven or eight, none of which may be termed prseanal. 



Uniform dark brown above; dirty yellowish grey below, 

 with dark döts or marblings on each plate. 



One specimen, a male, taken at Pelechucio, Western 

 Bolivia, under a stone, ^Vs 1904. E. Nordenskiöld and N. 

 Holmgren. 



Measurements : total length 54 + 84 mm.; length of head 

 12 mm; breadth of head 9 mm; from end of snout to före 

 limb 19 mm; length of före limb 14 mm ; length of hind limb 

 21 mm. 



From the ' evidentlj^ nearly allied Proctoporus unicolor 

 Gray from Ecuador this species seems to differ in the follow- 

 ing points: The supraoculars in my specimen are only two 

 (three in P. unicolor), the median occipital in the former 

 half as broad as the lateral ones, in the latter »frequently 

 absent or very small», the chin-shields in P. unicolor are one 

 anterior and four pairs and beside these »an additional pair», 

 in my specimen a single anterior and only two pairs without 

 any additional median one. Prseanals five or seven in the 

 posterior row in P. unicolor, six in my specimen. Femoral 

 pores in P. unicolor 9 — 12 among which »one or two may be 



