88 Godwin- Austen — Descriptions of Ahjcceince. [No. 1, 



portion of the last whorl, the sculpture terminating abruptly both 

 in front and behind with the exception of some raised strise close 

 behind the termination of the sutural tube ; indistinct ribbing near 

 the umbilicus. Spire conoid, apex obtuse ; suture impressed ; 

 whorls 4-4^-, rounded, last very slightly swollen, constricted and 

 enlarging slightly again near the aperture. Constriction smooth, 

 rather short ; sutural tube moderate commencing at *045 inch dis- 

 tance from the mouth. Aperture slightly oblique, a perfect circle ; 

 peristome double, thick, inner continuous, projecting, slightly ex- 

 panded, the outer retrorelict. Operculum horny, multispiral, con- 

 cave in front ; smooth behind, no central boss. 



Ordinary size.-— Major diam. 0-12" to 0-13".— Minor diam. 0*11*. 

 — Alt. 0-10" to 0-11". Diam. of aperture 0-06".— Sutural tube, 

 0-045". 



Habitat. Was abundant on the Limestone Hill east of Kopili 

 river, North Cachar District, and was occasionally also found in 

 other places, but rare. 



This shell is very close to Alycceus vestitus, W. Blanford, but 

 differs in its smaller size, the ujyper whorls being quite smooth, 

 and in the ribbing near the sutural tube being more strongly and 

 coarsely marked and in ending abruptly with it. 



Alycseus diagonius, n . sp. PI. Ill, fig. 2. 



Shell closely umbilicated, turbinate, thin, translucent, pale am- 

 ber or pinkish colour, finely but distantly costulated on the two last 

 whorls, closely so on the inflated portion of the last. Spire conoid, 

 apex blunt, suture well impressed, whorls 4, rounded, constricted 

 closely near base of the sutural tube, then swelling largely to- 

 wards the mouth, the commencement of the swell forming a diago- 

 nal or recurved ridge above. Constriction smooth, sutural tube 

 0-053 inch ; aperture diagonal, circular, peristome sinuate, double, 

 inner lip continuous, outer expanded, slightly reflected at umbilicus 

 and partially concealing it. 



Operculum concave in front, convex behind with a small central 

 boss or neucleus. 



Major diam. 0-145".— Minor diam. 0- 120 .—Alt. 0-10".— Diam. 

 of aperture, 0-75". 



