Pvn H,i I'UitlS

AVICULID^E. 93
aid of winds or insects is almost always necessary to
ensure propagation.
It is to be hoped that some expe-
rienced physiologist will investigate the subject in all
its bearings and set at rest this long-agitated question.
L. Mans differs from L. Loscombii in its much larger
size, being more depressed, and widely gaping at both
sides instead of at the dorsal side only. It is the L.
jrag His of Fleming, L. vitrina of Brown, L. aperta of
Sowerby, L. inflata of Forbes, and L. tenuis of Leach.
The original describer of the species was Schroter ; but
the name he gave it, being in his own language, is not
admissible according to scientific rules. The Ostrea
tenera of Chemnitz is a West Indian species of Lima and
very different from the southern variety of L. Mans.
I found a very small and imperfect single valve of
L. inflata (Philippi) in trawl-refuse from the Plymouth
coast. It is rather common in the Mediterranean. The
shell is tumid and very strong for its size ; the surface
is coarsely decussated or reticulate by strong longi-
tudinal ribs and transverse plates ;
ably small ;
the ears are remark-
and the hinge is furnished with a horizontal
cartilage-pit as in Pecten. Lamarck's species
of the
same name is distinct from this ; and according to him
it inhabits " POcean americain."
** Mantle open in front, and forming at the posterior side
(rarely at both sides) one or two tubes, which are mostly
sessile.
Family IV. AVICU'LID^E, Swamson.
Body obliquely oval or oblong, compressed : mantle open,
and free at its edges, which are fringed with cirri : foot small
and cylindrical, furnished with a byssal groove.