BIVALVIA. 135 
reference he is probably correct, and I have, therefore, had figured one of my small 
specimens which seems to correspond with the xodosum of Turton. The recent shells 
called nodosum and fasciatum being kept separate by conchologists, I have here, in defer- 
ence, done the same, although, I confess, not without misgivings. Dr. Lovén (‘ Ind. 
Moll. Scandin.,’ p. 35), when describing C. fasciatum and others, says, “ Cardia Huropea 
misere confusa,”’ and I feel disposed to echo his words. 
Mr. Jeffreys, in his list to Mr. Prestwich’s paper (p. 138), introduces C. Worvegicum 
as a new Cor. Crag species, but no locality is attached to the name; and in his list of 
Red Crag shells in the same paper (p. 482) Card. interruptum is referred to this species 
(viz. C. Norvegicum). If this be the form upon which the name Worvegicum is thus 
introduced as a Corélline Crag species, it will not require another figure; but I have not 
yet been able to see a shell like C. interruptum from the Coralline Crag, or to refer any of 
my specimens satisfactorily to C. Morvegicum. 
Carpium Parkinsont, J. Sow. Crag Moll., vol. ti, p. 158, Tab. XIII, fig. 7. 
Localities. Red Crag, Walton, Sutton, and Butley. 
This species is exceedingly abundant at Walton, but rare in other parts of the Red 
Crag. Dr. Woodward, in his list in ‘ White’s Directory,’ gives it (in fragments) from the 
Fluvio-marine Crag of Thorpe-by-Norwich, but I have not seen the shell from that Crag, 
and suspect that the fragments referred to are those of the large individuals of edule so 
common in the Norwich Crag and Lower Glacial sands. Parkinsoni much resembles 
C. Nuttall, Conrad, a shell living in the seas of Upper California (‘Journ. Nat. Hist. 
Soc. Boston,’ vol. vii), but I believe our Crag shell to be distinct, as it is less oblique, 
with fewer and broader ribs, and these are united at their bases, while the ribs in 
Nuttalli have a distinct space between them. In both species the ribs are imbricated. 
CarpiuM Decorticatum, S. Wood. Crag Moll., vol. ui, p. 159, Tab. XIV, fig. 1. 
Localities. Cor. Crag passim. 
This is abundant in a fragmentary state m the Cor. Crag, but perfect specimens are 
difficult to obtain ; it was a handsome shell, and fragments indicate a length of 33 inches. 
C. venustum resembles it, and may possibly be the same species ; but, as I have before 
stated, it is a smaller shell and smoother, the ribs in decorticatum being prominent and 
distinct. In the list annexed to Mr. Prestwich’s Cor. Crag paper this shell is referred to 
C. levigatum, Poli, but in the list to the Red Crag paper it is referred to C. Norvegicum. 
I cannot, however, agree in either reference; and have not seen it from the Red Crag, 
but only the allied form venustum. 
