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PHTSID^. 127
'25S. Planorbis (Segmentina) calathus (Bensoii).
Pkmorbis {Seqmentina) calathus (Benson), A. M. N. II. ser. 2, v,
1860, p. 348; II, & T., 0. I. pi. 34, figs. 1-3: Sowerby, in
Reeve, Concli. Icon, xx, pi. 4, fig. 30; Clessin in Concli.-Cab.
1884, p. 130, pi. 15, fi-. 1.3.
Orifjinal description:—Testa nitidiuscula, albido-cornea, vel
3utescente cornea, siibdiaphana, exilifer radiato-striafa, supra convexa,
versus apicein planulafa, apice coiicavo, sutura impressa ;
Tinfr. 4, ultimo extus depresso, inferne angulato, intus lamiuis
denticulisque radiatis freqnentioribus munito, subtus subplanato,
versus umbilicum angustum, profundum excavate; apertura
obliqua, cordate sagittata intus remote labiata, margine superior!
•arcuate, prominente, iut'eriori subrecto, i-ecedente.
Alt. 2, diam. maj. 4'66, diam. min. 4 mm.
Hah. Bbimtal and Neini Tal, in the Kemaon Region of the
Himalayas ; Meradabad ; Kattiawar ; Ceylon; Kashmir, etc.
Apparently very local, but abundant where found.
-259. Planorbis (Segmentina) csenosus (Benson).
Planorbis (Segmentina) ceenostis (Benson), A. M. N. 11. ser. 2, v,
1850, p. 349; II. & T., C. I. pi. 39, figs. 7, 8; Sowerby, in
Reeve, Ooncli. Icon, xx, pi. 10, fig. 78; Clessin, in Conch.-Cab.
1884, p. 165, pi. 24, fig. 4.
Original description:—Testa nitida, luteo-cornea vel olivaceo-
•cornea, oblique et rude (prjecipue subtus) radiato-striata, sub-
•diaphana, supra depresso-convexa ; spira parvula, apice excavate ;
«utura impressa; anfr. 3|, ultimo majori, extus depressiuscule,
inferne earinato, subtus planate, versus umbilicum majorem
leviter excavate ; apertura ebliqua, sagittiformi, margine superieri
arcuate, prominente inferior! recedente, recto.
Alt. 1'6, diam. maj. 6, diam. min. 5 mm.
Hab. Meradabad ; Ceylon'.
Differing from P. (S.) calathus in having no internal laminse and
in being more depressed and more angular at the keel ; moreover
-the relative dimensions are not the same.
Family P.HYSIDJi.
Subfamily PHYSINiE.
^5hell fusiform or ovately fusiform, sinistral, horny.
Distribution. AVorld-wide.
Genus PHYSA.
JVtt/.ia, Braparnaud, Tabl. Moll. France, 1801, p. 52, & [list. Nat.
iloll. Terr. Fhiv. France, p. 54.