t^^l

pisiDiuJi. 225'
TrpB, Fisidiuni anuiicum, Jenyiis, from Europe aud JXorthern
Asia.
llange. World-wide.
Shell small, roundly ovate or obliquely wedge-shaped, inequilateral
; anterior side longer than the posterior; umbones slightly
inflated behind; hinge bearing two cardinal teeth in each valve:
right valve bearing four laterals and the left valve two ; lateral
teeth strong; ligament situated on the smaller (posterior) side ;
pallia! line entire.
Animal having the mantle lobes smooth and open; furnished
with a single short (anal) siphon, with non-papillary orifice ;
bi'anchial cavity indistinguishable from the pedal cleft ; foot
large, tongue - shaped, capable of great extension ; palpes
triangulai-, elongated.
367. Pisidium clarkeanum, G. c|- tf. Neuill.
Pisidium clarkeamtm, G. & H. Nevill, J. A. S. B. xl, 1871, p. 9,
pi. 1, &gi. 4, 4 ff-4 d.
Original description:—Testa ventrieosa, oblonga, valide insBquilateralis,
pallide fulva ; postice elongata ac rotnndata, anticer
rotundate truncata ; umbonibus prominentibus ac tuniidis ; superficie
concentrice confertira striata, striis tenuibus, regularibus.
Long. 4-5, lat. 5'5, diam. 8'5 mm.
Hah. Tanks, etc., close to the Damuda at Moisraka.
368. Pisidium hydaspicola, Theobald.
Pisidium hjdaspicola, Theobald, J. A. S. ]3. xlvii, 1878, p. \AT.
Original description ;—Testa sub-cordate ovali- tenui, exilissime'
striata, antice rotundata, postice vix truucata.
Long. 3-4, lat. 4, diara. 2"5 mm.
JIa(>. Kashmir, near Shypion.
Fig. 27.—Pisidium hydaspicola, Theob. (Type.) x4.
To the above scanty description is added the following note:—
" The nearest ally of this species is P. clarkeanum, Xev., but it
more r.ounded in front and hardly truncated behind."
The type is in the British Museum.