276 MOLLUSCA FROM THE CRAG. 
mitted from the Older Tertiaries. M. Deshayes says the Paris Basin shell is un- 
doubtedly identical with the Touraine species; the latter corresponds more closely 
with the Crag fossil; the Kleyn Spauwen shell resembles more (as might be supposed) 
the Paris Basin variety. The Touraine specimens differ slightly from the Crag fossil, 
but not, I think, sufficiently to invalidate their identity. In our shell the siphonal 
side is not so pointed or keeled, and there is a little difference in the dental furniture, 
and the palleal sinus is a trifle larger. 
The ligament is placed in a fossette in the right valve, visible externally, when the 
valves are closed, through a sinus in the umbo; the left valve has a projection on 
which are placed both ligament and cartilage, separated by a ridge: before this 
ligament is a tooth in each valve. This was probably an estuary shell. The locality 
(Roydon), given for it in ‘Min. Conch.,’ is an error. 
SpHENIA BineGHamt? Zurton. Tab. XXIX, fig. 7. 
Spuenrta Brncuami. Turt. Brit. Biv., p. 36, t. 3, figs. 4, 5; and t. 19, fig. 3, 1822. 
Spuani1a Bincuami. Forb. and Hanl. Hist. Brit. Moll., vol. i, p. 190, pl. 9, figs. 1—3, 
1848. ; 
CorsuLa Binauami. Hanley. Recent Shells, p. 47; Supp., pl. 12, fig. 4. 
— — Woodw. Man. of Moll., vol. ui, p. 318. 
Spec. Char. Testa minutd, transversd, cuneiformi tenui fragili, levigatd, valde 
inequilaterali ; antice rotundatd, posticé angustd, subrostratd. 
Shell small, transverse, wedge-shaped, thin and fragile, smooth, and very inequi- 
lateral; anterior side rounded ; posterior produced and somewhat pointed. 
Length, ~ inch. 
Locality. Cor. Crag, Sutton. Recent, Britain ? 
The genus Sphenia has been founded upon a single species of Mollusc inhabiting 
our own shores, and is at present not well established: the animal has been examined 
by Mr. Clark who says it is quite distinct from Mya or Savicava, though not far removed 
from either; perhaps still nearer to Cordula. 
Only two or three specimens, and those not in very good condition, are in my 
Cabinet ; they will not throw any light upon the obscurity which hangs over the 
recent shell. 
My best specimen has a spatulate tooth in the left valve, like that in the young of 
Mya, which it resembles in some characters, but it is much thinner, with something of 
a nacreous appearance; and the outline also is different from that of the young of A/ya 
of the same size: mine is, however, a very doubtful identity of the existing species. 
