62 [April, 



The Committee on Dr. HallowcH's paper describing new species 

 of Reptiles, reported in favor of publication in the Proceedings. 



Descrlptio7i of netif species of Keptilia from Western Africa* 

 By Edward Hallowell, M. D. 

 PHRACTOGONUS,* Halloivell. 



Snbgeneric Characters. Head conical, presenting two large plates upon its 

 upper surface. Nostrils below the rostral. A row of longitudinal shields upon 

 the chest. Body and tail annulated ; lateral pores near the anus. 



Phractogonus gahatus. 



Specific Characters. Five teeth in the lower jaw on each side ; four maxillary 

 on each side of the upper jaw, and two intermaxillary teeth; two large plates upon 

 the head; lateral pores near the anus; pectoral shields four in number, long 

 and narrow; two hundred and fourteen rings upon the body, eighteen upon the 

 tail. 



Description. The head is small and somewhat triangular, rounded in front. 

 It presents upon its upper surface two large plates, one of which forms the ros- 

 tral. The posterior of these is much the larger, and is more extended 

 transversely than in its antero-posterior diameter. It presents three 

 distinct margins anteriorly, its posterior margin being somewhat 

 rounded ; its superior surface is convex. The rostral is rounded an- 

 teriorly, depressed above ; its anterior margin presents an acute edge. 

 The snout extends nearly a line beyond the mouth. In an angle formed by the 

 plates just described, on each side of the head, is one which is narrow and 

 oblong ; and immediately behind it another very small and quadrilateral ; behind 

 this at the angle ofthe mouth is a triangular plate, its base presenting back- 

 ward ; between them at the posterior part of the head are four narrow and 

 more or less oblong and two smaller ones. The nostrils are 

 quite small, V shaped, a line apart, and are situated upon the under 

 part of the snout, in a narrow plate immediately behind the 

 rostral. The eyes are not visible. Five labial plates margin the 

 upper jaw on each side. There are three upon the margin of the lower 

 jaw', tfe posterior of which is very large and quadrilateral. The mental 

 plate is also large, with a rounded posterior margin. The pectoral shields 

 are four in number, the two middle ones by their junction forming a tri- 

 angle superiorly. They are each about three lines and three-fourths in length, 

 and a line in breadth. The two lateral shields, which are pentagonal, have their 

 /^.ys. bases precisely in aline with those of the intermediate plates. Im- 

 /\X-J\ mediately above the two middle pectoral are two small quadrilateral 

 J r T ones about a line in breadth ; their external and inferior margin is 

 j I "in contact with the superior and internal margin of the long and 



' V I J / narrow external pectoral shields. There are nine semicircular 

 rings upon the upper part of the body terminating at the base ofthe 

 pectoral plates. There are 214 rings upon the body, and 18 upon the tail. 

 Body slender, cylindrical, fifteen lines in circumference at its middle, of an 

 obscure white color : (the specimen has been preserved in alcohol). The back 

 of the animal is covered with numerous small quadrangular scuta, looking 

 ^ I j j-p, like mosaic : they are wider apart upon the abdomen, which has a 

 V' '^JJ.^Jtg/ smooth appearance. No longitudinal sulci are observed upon the body. 

 There are two lateral pores quite distinct, each in a separate scale 

 on the left side of the row of pmnanal scales, and one near the centre of a scale 

 on the right ofthe same row. The scales in front ofthe anus are six in riumber, 

 the two middle ones oblons; and quadrilateral, the lateral ones irregular in shape. 

 Biviensioiis. Length of head Ah lines, of neck and body 13 inches (Fr.) 10 

 lines, of tail l-Oi lines. 



Geographical distribution. Liberia, West Coast of Africa. 



<I>/i*xTof munitus, ymoi; angulns. 



