245 
Venus. 
,re mostly on one side, rarely immaculate : beaks near one 
end, without the heart-shaped impression under them ; in¬ 
side white, with the margin obtuse and plain : teeth three 
in each valve, the middle one only cloven : length an inch 
and a half; breadth nearly two. 
The outline of this shell Is much like the last; but is 
more convex and not so much elongated, nor so coarse * 
the reticulations are finer ; the ground-color is cf a more 
delicate white, and the colored marks are generally crowded 
towards the elongated end ; the middle tooth only"is cloven $ 
the lateral ones being thin. 
Equally common with the last. v. v. 
2S. Venus perforans. Perforating Venus. 
Montagu, pi. 3. f. 6. 
Shell somewhat rhombic, convex* coarse, elongated and 
a little angular or truncate at the cartilage side, often much 
distorted and variously indented, a little gaping at the up¬ 
per angle of the elongated side, white or pale brown, marked 
with transverse strife which run into rough raised ridges or 
wrinkles on the longer side, with sometimes a few faint lon¬ 
gitudinal ones, but not regularly reticulate; the cartilage 
long and straight; inside glossy white, with often a purple 
stain on the cartilage end ; tlic margin thin and plain : 
beaks near one end, turning a little to the shorter side: 
hinge with three teeth in each valve, one of them small, the 
others long slender recurved and slightly cloveni 
Burrowed in limestone, at Plymouth, and Hoath in Ire¬ 
land. In the red calcareous sandstone about Teignmouth, 
in Devon, they are found lodged in aburidance about low 
water mark, more than an inch long and nearly two broad: 
but in general they ai-e aboil t half the size. v. v . 
29. Venus substriatm Bub striate Venus . 
Montagu , pi. 29. f. 6i 
Shell transversely oval, white, semitransparent, concen¬ 
trically wrinkled, and marked with obscure undulated lon¬ 
gitudinal striae; inside moderately concave and smooth, 
with the margin plain: beaks hearer to one end, small, turn¬ 
ing to one side : hinge with three teeth ; thflt which is next 
the cartilage long, oblique, and forming a cavity between it 
V 3 and 
