PLECTOPYLIS. 



137 



Helix (Atopa (Plectopylis}) anguina, Tryon, Man. Conch, ser. 2, iii, 



1887, p. 165, pi. 35, fig. 0. 

 Plectopylis (s. s.) anguina, Gude, Science Gossip, N. s. vi, 1899 



p. 148. 



Original description : " Testa sinistrorsa, distorta, planorboidea, 

 glabra, fusco-castanea ; infra radiatim flainmulata, vix concava; 

 spira planulata ; anfr. 5| convexiusculis, ultimo ad peripheriam 

 sub-angulato ; apertura despecta, perobliqua, semi-elliptica, peri- 

 stomate rufo, revoluto, callo angulato baud appresso, coDJuncto ; 

 lamella alba secundum anfractum penultimum intro-volvente. 



"Diam. 1 poll. [=25'5 mm.]; alt. J poll. [=6-25 mm.]." 

 (Gould.) 



Hab. Burma: Manko, Tavoy (Vinton); Kuengan (Tlieolald) ; 

 Sgwagakin, Salween Valley (Coll. Ponsonby). 



By some authorities this species has been considered identical 

 with P. bensoni. It appears, however, to be perfectly distinct. 



The shell is sinistral, much flattened, discoid, varying in colour 

 from corneous to dark chestnut ; below it is usually paler and 



Fig. 69. Plectopylis anguina. 



flammulated with dark chestnut; it is finely striated and de- 

 cussated by microscopic spiral lines. The spire is depressed, the 

 suture linear. Whorls 5J, regularly coiled, increasing slowly and 

 gradually ; slightly flattened above and rounded below. The last 

 whorl is slightly angulated at the periphery, widening rather 

 suddenly at the aperture, deeply deflected in front, and somewhat 

 constricted behind the peristome. The umbilicus is extremely 

 shallow ; in a specimen in my collection it is only 1*5 mm. in 

 depth. The aperture is nearly horizontal, cordate ; the peristome 

 livid or pale brown, a little thickened and much reflexed. A 



