248 VENUS. 



and the margin for the reception of the cartilage ; the other 

 two short, the middle one the longest : length half an inch ; 

 breadth something more. 



In the Firth of Forth : very rare. 



30. Venus subrhomboidea. Rhombic Fenus. 

 Montagu, pi. 28. f. 2. 



Shell somewhat rhombic, rounded at one end ancTtrun- 

 cate at the other, irregularly wrinkled transversely, espe- 

 cially towards the margin where the wrinkles are prominent 

 but obtuse, and crossed by fine close-set longitudinal lines : 

 color white, with a rufous tinge at the truncate side ; inside 

 white, purplish where the rufous tinge is on the outside, 

 with a plain margin : beaks small, nearly central, inclining 

 to one side : hinge with two strong plain teeth in each valve, 

 one of them very oblique; behind these the margin projects 

 inwards, and then folding back forms a smooth reflexure, 

 and a cavity between it and the outer edge of the shell be- 

 hind the beaks for the connecting cartilage : length half an 

 inch ; breadth three-quarters. 



It much resembles the Donax Irus ; but that shell is 

 always furnished with two cloven teeth in each valve, besides 

 a plain tooth in one of them : and the transverse ridges in 

 this are more obtuse and not so laminar. 



Firth of Forth : very rare. 



31. Venus virginea. Maiden Venus. 



Lister, pi. 403. f. 247, and pi. 404. f. 248 Pennant, 

 pi. 58. f. 5 Linn. Trans, viii. pi. 2. f. 8 Dorset Cat. pi. 13. 



Shell rhombic oval, much produced at the cartilage side 

 and rounded at both, with numerous regular concentric 

 somewhat imbricate striae, interrupted by a few antiquated 

 furrows : color glossy yellowish-white or pale reddish- 

 brown, sometimes plain, but mostly variegated and marbled 

 with rosy or rich purple, sometimes streaked or spotted, 

 and sometimes with broad oblique purple longitudinal rays, 

 rarely pale rosy with two or three white rays ; inside white, 

 with often a rosy tinge about the hinge, the margin plain 

 and obtuse : beaks near one end, a little turned to the 

 shorter side, with a long and narrow impression under 



them : 



