VENUS. 241 
them. In the second plate of.the eighth vol. of the Linnean 
Transactions, these two are placed together, exhibiting their 
different appearances. 
Western coasts : very rare. v. m. 
21. Venus orhiculata. Orbicular Venus . 
Montagu , pi. 29. f. 7* 
Shell orbicular, rather flat, white, striate longitudinally 
and transversely 5 inside white, with the margin plain : 
beaks extremely small, with a minute heart-shaped depres¬ 
sion under them: hinge with two teeth placed together, 
and a remote one standing transversely; the margin where 
the lateral tooth is placed projecting into an angle : diame¬ 
ter five-eighths of an inch. 
It has much the appearance of the last, but is not so flat, 
is more rounded and more coarsely reticulate, and the la¬ 
teral tooth is much more remote. 
Found by Captain Laskey, near Dunbar: very rare. 
22. 'Venus undata. JVetoed Venus. Fig. 54. 
Pennant , pi. 58. f. 3 —Donovan, pi. 1 21—Linn. Trail?. 
vi. pi. 17 . f. 17 , 18. 
Shell very thin and transparent, rather convex, yellow¬ 
ish white with mostly a ferruginous tinge, marked with 
fine irregular transverse stria* or wrinkles, a little irregu¬ 
larly undulate round the circumference; inside glossy yel¬ 
lowish-white, with the margin very sharp edged and plain : 
beaks prominent, rather pointed, very little inclining to one 
side, without the heart-shaped depression under them : 
hinge with three teeth in one valve, and two in the other : 
length above an inch; breadth rather more. 
Western coasts, and Dublin bay. v. v. 
’• 1 
> 23. Venus exoleta. Antiquated Venus . 
Lister, pi. 291. f. 127, and pi. 293. f. 129— Pennant , 
pl- 57- f- 3— Da Costa , pi. 12. f. 5— Donovan , pi. 42. f. 1 — 
Dorset Cat. pl. 8. f. 5— Linn. Trans, vi. pl. 17- 10, and 
viii.pl. 3. f. 1. 
Shell strong, orbicular, flattish, often a little angular to¬ 
wards the front margin on the cartilage side, with extremely 
fine and regular close-set transverse striae, and a few deeper 
Y antiquated 
