OSTREA. J31 
the margin crenate within: length nearly two inches ; 
breadth one and a half. 
On the sandy shores of England and Ireland, sometimes 
fixed to rocks, and sometimes entirely imbedded in hard 
limestone, v. v. 
6 . Ostrea fragilis. Brittle Scallop. 
Lister , pi. 1 77- f* 14. 
Shell oblong-oral, rather convex, milk-white but not 
glossy, brittle, semitransparent, with about twenty-five lon¬ 
gitudinal and somewhat undulated lines or fine ribs, and 
two or three minutely finer ones between each of them: 
valves equal, with the sides unequal, one being straight, 
the other produced and somewhat angular : hinge a little 
oblique: beaks pointed, prominent, reaching a little beyond 
the margin of the hinge, but not meeting together when 
the valves are closed, in consequence of the thickened in¬ 
ner transverse margin, with an oval hollow between them ; 
ears small, equal, smooth : inside white glossy, striate lon¬ 
gitudinally, with the front margin slightly undulated rather 
than notched: length three-quarters of an inch ; breadth 
not quite half an inch. 
This is the only British species which has the cartilage 
placed externally, in the hollow between the beaks, and 
not as in the rest, in an oval internal cavity. 
Devonshire coast: very rare. v. in. 
/. Ostrea subauriculata. Small-eared Scallop. 
Montagu, pi. 29. f. 2. 
Shell oval-oblong, white, transparent, with numerous 
longitudinal stria?, two of them running down the middle 
and appearing more conspicuous than the rest from their 
kingopake, and are equally visible on the inside : valves 
equal, with the sides exactly equal; the margin slightly 
crenate: ears very small, equal: hinge exactly in the mid¬ 
dle, and not sloping to one side as in the last: length a 
quarter of an inch ; breadth half as much. 
On the Devonshire coast: very rare. v. m. 
8 . Ostrea laevis. Smooth Scallop. 
Montagu , pi. 4. f. 4. 
Ostrea similis. Laskey, IVern. Soc. i. pi. 8 . f. 8 . 
Shell 
