196 CATALOGUE OF THE MOLLUSCA 
towards the lower part, where it gradually unites with the out- 
line of the body ; anal aperture tubular and prominent, situated 
about one-third down the side ; both are quadripartite and of a 
deep red colour. Outer tunic very thick, tough, and rugose, 
tuberculated and furrowed in an irregular manner; inside 
smooth and shining. Inner tunic bluish white, streaked with 
rose-colour at the apertures, and tinged with red in the centre 
from the ovaries shining through ; these last are round granu- 
lated protuberances of a red colour, studding the inside of the 
tunic in longitudinal rows. Branchial sac, with about twelve 
strong longitudinal folds, and finely reticulated, without papille 
at the intersections. Tentacular filaments, round the entrance 
to the branchial cavity, simple and linear. Length, two inches ; 
breadth, an inch and a half. 
Oynthia tuberosa, Macg. Moll. Aberd. 311 ; Forb. and Hanl. 
Brit. Moll. i. 37. 
From the fishing boats at Cullercoats, not uncommon. 
The characters here given agree pretty well with the Cynthia 
tuberosa, Macg., and we therefore follow the opinion of Professor 
E. Forbes in considering ours to be a larger state of that species. 
We have never, however, seen the tubercles so prominent as Pro- 
‘ fessor Macgillivray describes; and the tubular apertures are 
very conspicuous when the animal is expanded in sea-water : 
when removed from that element, they, as well as the whole body, 
contract greatly, in which state they agree better with Professor 
Macgillivray’s description. ‘This species is often covered with 
corallines and other small marine bodies, and the Modiola mar- 
morata is usually found imbedded in its skin. 
2. C. cornraczea, Ald. and Hane. 
Body elongated and cylindrical when extended, nearly hemis- 
pherical when contracted, of a pale brownish colour, attached to 
shells, &e., by a broad base, equalling the diameter of the body. 
Apertures, terminal, approximating, tubular, nearly equal in size, 
pale, with a faint line of red round the margins. Outer tunic 
rough, coriaceous, transversely wrinkled and longitudinally fur- 
rowed, covered with minute granules. Inner tunic thin, white, 
sometimes spotted with brown. Ovaries large and white, lining 
