Pvn H,i I'UitlS

VENUS. 331
Var. compta. Shell smaller, more elongated, with coarser
ribs and stronger teeth. Artemis compta, Lov.Moll. Scand.p.39.
Habitat :
Sand, sometimes mixed with mud, on every
part of the British coasts, from low-water mark to
90 fathoms, occasionally associated with the last species.
Var. compta. Single valves only, from Skye (Barlee) ;
Shetland (J. G. J.). V. lincta is fossil in all our upper
tertiaries, from the so-called "alluvial" stratum in Belfast
Harbour and the boulder-clav of Wick to the Red. and
Coralline Crag, as well as in the redeposited Crag-bed
of Aberdeenshire. Iceland is its most northern known
boundary, and the iEgean
and both sides of the Medi-
terranean the most southern. Philippi noticed its occur-
rence in the South- Italian tertiaries.
Lister, in his ' Historia Conchyliorum/
well distin-
guished this species from V. exoleta, as "rostro production,
capillaceis fasciis donatus." It is smaller, more
convex and glossy, the laminar ribs are much more
numerous, the posterior side is somewhat flexuous,
it is
destitute of the coloured markings peculiar to the other
species, and the umbones are more prominent. The
small anterior teeth have more the appearance of short
laterals, and may be analogous to those of Circe. My
largest specimen does not much exceed an inch and a
half in length. Monstrosities sometimes occur : a specimen
now before me is nearly globular, with consequently
a much more abbreviated lunule ; and Mr. Norman pos-
sesses one which is remarkably inequivalve.
The description of V. lupinus in the tenth edition of the
'
Sy sterna Naturae' (although not of the variety "maculis
griseis ") may possibly have been intended for V. lincta;
but no locality is assigned to it. Poli adopted the
former name for the present species ; Lamarck called it
Cytherea lunaris ; Turton V. sinuata ; and Risso Arcto'e