VENUS. 24 f> 



:ic mostly oil 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 of 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. 



28. 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 striae 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; the margin thin and plaint 

 beaks near one erid, 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 cloven- 

 Burrowed in limestone, at Plymouth, and Hoath in Ire- 

 land. In the red calcareous sandstone about Teignmoutb, 

 in Devon, they are found lodged in abundance about low 

 water mark, more than an inch long and nearly two broad : 

 but in general they are about half tne size. v. v, 



29. Venus substriata, Stihstriate Venus. 

 Montagu, pi. 29. f. 6. 



Shell transversely oval, white, sdmitransparent, concen* 

 trically wrinkled, and marked with obscure undulated lonr 

 gitudinal striae ; inside moderately concave and smooth, 

 with the margin plain: beaks nearer to one end, small, turn- 

 ing to one side : hinge with three teeth ; that which is next 

 the cartilage longj, oblique,, and forming a cavity between it 

 Y 3 and 



