CARDIUM. 101 
C. rasciatuM, Montagu. 
C. fasciatum, Brit. Moll. ii. p. 25, pl. 32. f. 5; (animal) pl. N. f. 3. 
C. elongatum, Auctorum. 
Animal suborbicular, body flake-white; mantle plain. Si- 
phonal tubes not exserted usually above $th of an inch, of 
the same length, united, each with ten simple white cirrhi, 
and on them are the invariable filamentous appendages. The 
foot is long, narrow and subcylindrical, or finger-shaped, and, 
contrary to the Cardia in general, hyaline. The branchie 
are subsemicircular, pale brown, the upper one not half the 
size of the lower, strongly striated on the outside and smoother 
within; the palpi are very short, triangular but poimted, 
striated on the outer, and much less on the inner surface. 
The liver is green and very anterior; the ovarium white, and 
full of ova on 4th of August. 
It inhabits the coralline zone, and is rare at Exmouth. 
C. novosum, Turton. 
C. nodosum, Brit. Moll. ii. p. 22, pl. 32. f. 7. 
C. muricatulum, juv., Auctorum. 
Animal subglobose ; mantle open, edged with white pomted 
filaments issuing from the points of the mantle corresponding 
to the ribs. The siphons are pale yellow and very short, each 
with ten or twelve flake-white cirrhi at the orifices and red 
points at the bases, with the addition of the curved white 
filaments above, below, and on the tubes; the anal one pro- 
trudes the usual retractile valve. The foot is white, mode- 
rately long, subcylindrical, and slightly geniculated. There 
are a pair of semi-oval branchiz on each side, the upper is 
not half the length and breadth of the under one; they are 
strongly pectmated on the upper, and less on the lower 
surface; there are two very small triangular palpi on each 
side, pectinated in a similar manner with the branchiz. 
This species, at Exmouth, is only met with in the coralline 
zone, but it is not uncommon. 
We have ascertained by a comparison of the C. muricatulum 
of authors, of sizes of less than ;!,th-ths of an meh dia- 
