PLANORMS. 



119 



not influencing tlie aperture, which is ovato-lunate ; umhilicus 

 wide, discoverino- all the previous volutions ; the \\horls rising 

 gradually and spiriilly from the horizontal, and rounded belou . 



Animal Ijlack or dusky. 



Hah. Kandahar, plentiful in tanks; Quettah and the Kojuek 

 Pass, in marshes, and along the marsldands of the Kiver Hehnund 

 at Girishk (IJutton)- Grangetic Provinces {Tope Vhancey); Pinjore, 

 below .Simla (Jfutton). 



It differs from Plunorhls com2yrei<sus in wanting the delicate 

 carina at the periphery and in having a lunate aperture without 

 the angle on the middle of the outer lip ; in being more convex, 

 with rounder whorls ; and in having its volutions wound round 

 on a more open and less horizontal twist. 



235. Planorbis (Gyraulus) labiatus (Benson). 



Planorbis (GyrauU(s) labiatus (TJeuson), A. M. X. II. ser. 2, Xy 

 1850, p. 850. 



Orhjincd description : — Testa solidiuscula, plano-depressa, nitida, 

 albido-cornea, subdiaphaua, oblique arcuato-striata, striis remotius- 

 culis spiralibus decussata ; apice profunde coucavo ; sutura 

 profunda ; anfr. 85, cito crescentibus, convexis, ultimo antice 

 majori, ab axe superiorum discedenti, rotundato, carina mediaua 

 levissima submembranacea instructo, infra valde couvexo ; 

 umbilico subaperto i^rofundiori, margine interiori subangulato ; 

 apertura obliqua, cordiformi, iutus albo-labiata ; margine superior! 

 arcuato, inferiori rotundato. 



Alt. scarcely 2, diam. maj. 5, diam. min. 4 nnn. 



Fig. r>.— Plan(jrhig (G/jraulus) Idhiatits, Bens. (Types.) 

 1, spire ; 2, base of shell. X 4. 



Hah. 31oradahad (found among specimens of Planovhis con)- 

 pressns. Hutton). 



'•This little shell is remarkable for the de])arture of the last 

 wliorl from the axis which governs tlie previous vohitions. This 

 is es))ecially apparent underneath, where the earlier whorls in the 

 umhilicus proceed regularly, the last whorl becoming suddenly 

 excentric. The whitish rib within the lip is also a marked 

 character, as well as the proportion of the axis to the diameter." 



