328 LAND AND FRESHWATER 



Shell perforation concealed, globosely conical, with a strong 

 epidermis, well rounded below, keeled ; sculpture regular longi- 

 tudinal liration, crossed by very fine transverse lines, coarse, con- 

 centric on base ; colour dull ochraceous ; spire high, conic, apex 

 fine, sides flat; suture rather shallow; whorls 6, regularly in- 

 creasing ; aperture oblique, semilunate, and fairly broad ; peristome 

 thin, the epidermis extending beyond the shell and somewhat thick- 

 ened ; columellar margin curving from the very slight reflection. 



Size : maj. diara. 5-25 ; alt. axis 3'6 mm 



Animal with a mucous gland and foot divided, visceral sac plain 

 near branchial sac, dark near apex. 



I was fortunate after soaking the dried up animal to get the 

 central portion of the radula. When perfect it must have a very 

 large number of teeth in the row. The three central teeth are 

 slightly larger than those tliat follow, and are tricuspid, the suc- 

 ceeding teeth are bicuspid, nearly evenly so, and have two smail 

 serrations on the outer margin as seen when the teeth are in a 

 certain position. 



The shell and its sculpture differs considerably from S. rimicola 

 and attegia, which it approaches in shape, but its strong keel 

 distinguishes it at once from the first, while it is flatter on the 

 base and has a feeble columella, from the second it is smoother 

 and rounder. It was sent me in spirit by Mr. S. E. Peal with 

 other species some years ago. Peal's death in the prime of life 

 was a great loss — he was clever with his brush and pencil, a lover 

 of nature, and wrote some good descriptions of the Hill country 

 near which his tea garden was situated. 



Mr. M. Ogle also obtained this species at Sadia, Xo. 3280 B.M., 

 and in the Dihing Valley, No. 3278 B.M. 



Subfamily Durgellin^. 



Genus Dtjrgella. 



{Continued from Vol. II. p. 293, 1910.) 



Dtjbgella nahaeaniensis, n. sp. (Plate CXXXV. figs. 2-2 c). 

 No. 2320 B.M. Coll. 



Locality. Naharani, Upper Assam, March 1884 {S. E. Peal). 



Shell scarcely perforate, very globose, smooth, shiny, very thin 

 and membranous ; sculpture to the naked eye, crossed trans- 

 versely by regular undulations of growth, longitudinally under high 

 power by indistinct striation broken off by the first. Colour bright 

 brown, first whorl at apex white. Spire scarcely rising above the 

 last whorl ; suture very shallow ; whorls three, rapidly increasing, 

 rounded on the periphery : aperture roundly ovate ; peristome 

 thin ; columella margin weak, curving inwards. 



Size : maj. diam. 6"75, min. 5'4, alt. axis 3 mm. 



Animal (tigs. 2-2 h). Foot long, narrow ; peripodial fringe broad, 

 regularly grooved, three peripodial lines, thus as in D. assamica. 



