26 PROSOPEAS. 



the first two or three whorls, the riblets weaker near the 

 upper suture. On the later whorls the sculpture is of very 

 fine, densely crowded striae, quite oblique, and arched forward 

 below the suture. Where fresh and unrubbed, there are min- 

 ute and delicate cuticular hairs arranged in spiral lines on 

 the striae; when rubbed off, these hairs leave very slight de- 

 pressions visible as weak spiral lines in a favorable light. 

 The strige and hairs hold a thin coating of earth, giving the 

 shell the appearance of having a dull brownish cuticle. The 

 columella is narrowly reflexed and adnate. The parietal cal- 

 lus is so thin as to be hardly visible. 



P. paioense is related to P. laxispirum, but is larger, more 

 robust, with a thinner parietal callus. 



19, P. LAXISPIRUM (Martens). PI. 3, fig. 92. 



Shell imperforate, subulate, rudely striate, dull brown, 

 opaque; apex very obtuse. Whorls 11, the first a little con- 

 vex, subglobose, the following, from the fifth, flattened, elon- 

 gate; suture very oblique, somewhat channelled, distinct; last 

 three whorls subequal; base noticeably tapering. Aperture 

 slightly oblique, narrowly piriform, the columellar margin 

 white, reflexed and adnate throughout, passing above into a 

 distinct parietal callus, slightly twisted below and obliquely 

 subtruncate. Length 27 to 30, diam. 5 to 5.5 mm. ; aperture 

 6 to 7.5 mm. high, 2.5 to 3 wide. Length of the visible part 

 of the last whorl to the penultimate as 1 : 1% or 1% (v. 

 Marts.). 



Sumatra: mountains of the interior at Kepahiang, on the 

 ground; not rare (Marts.). 



Stenogyra laxispira v. MARTS., Ostas. Zool., Landschn., p. 

 373, pi. 22, f. 14 (1867). Bulimus 1., PFR., Monogr., vi, p. 92. 



Distinguished by the size, rough sculpture, want of an um- 

 bilical chink, distinct parietal callus, noticeable truncation of 

 the columellar margin, but especially by the very slow increase 

 of the individual whorls in height and width, therefore re- 

 maining almost equal. Only the upper whorls are wider than 

 high, so far as their visible parts are concerned, the fifth 

 to last being as high as wide, whereby the whole shell appears 



