t^^l

122 r.iMXvEiD^TS.
243. Planorbis (Gyraulus) associatus, Westerlund.
rianorbis (Gyraulus) associatus, "Westerlund, in ^''ega Exped'.,
Vetenskapliga Jaktta^elser, iv, p. 205, pi. 4, fig. 17.
Original description :—Testa depressa, supra plana, centro \ix
impressula, subtus late convexiuscula (anfractus ultimus cireumciroa'altior
et spira sensiin profuudior), striatula, iiitidula, cornea ;.
anfr. 5, lente accrescentes, primi convexi, cseteri convexiiisc-uli,
sntura sat profunda disjunct!, ultimus sensim latior, iion dilatatus,
peripheria obsolete angulatus, uti-inque subiequaliter convexiusculus
; apertura obliqua, ovato, peristomate subincrassato.
Alt. 1'5, diam. 5-5-6"5 mm.
Hab. Point de Galle, Ceylon.
Almost certainl}'" a variety of P. (G.) demissus.
244. Planorbis (Gyratilus) elegantulas (Dohm).
Planorbis (Gi/raulus) elegantnlus (Dobrn), P. Z. S. 18.58, p. 134;
II. k T., C. 1. pi. 151, figs. 1-3.
Original deseription:—Testa discoidea, albida sub lente teiuiiter
striata, nitida, pellucida, supra convexiuscula, umbilicata, subtus
plana ; anfr. 4-5 lente accrescentes, ultimus infra medium obsolete
carinatus ; apertura perobliqua, sublunaris; peristomium rectum,
intus calloso-albo-labiatum.
Diam. maj. 4'75, diam. min. 4 mm.
Aperture : alt. 1 mm.
Hah. Ceylon.
245. Planorbis (Gyraulus) nanus {Sow.).
Planorbis {Gyraulus) nanus (Sow.), Sowerby, iu Reeve. Concli. Icon.
XX, pi. 9, sp. 75 ; Benson, V. Z. S. 1856, p. 186.
Shell pale fulvous, compressed, i-ather convex above, broadly
and deepl}^ umbilicated below; spire narrow, flat; whorls 3,
obliquely striated, rapidly increased, last very broad ; aperture
depressed, very bread, outer lip obliquely produced above.
{Sowerby in Seeve.)
Diam. maj. 11, diam. min. 10 mm. (fig. 75 a in Conch, Icon.).-
J/ah. India; subfossil, Tsoral Lake, Tibet {Captain II. Stracliey).
246. Planorbis (Gyraulus) rotula {Benson).
Planorbis {Gyraulus) rotula (Benson), A. J[. N. 11. ser. 2, v,.
I860, p. 351; H. & T., C. I., pi. 90, figs. 2, 3.
Original description;—Testa minuta, depresso-planata, apertissime
umbilicata, luteo-cornea, diaphana, impolita, spiraliter
obsolete striata; anfr. 55^, cylindraceis, lente borizontaliter increscentibus,
supra et subtus roqualifer apparentibus; ultimo ad
periphterium rotiindato, nullo mode angulato : sutura sp^"a infraque
profunde impressa ; umbilico mininie profundo ; apertura
vix obliqua, rotundato-lunata; margine superior! arcuato.