Fig. 



15. V. ovata, Pennant. — Brit. co. generally, C. Oval, radiately 



ribbed. 



16. V. striata, Donov. — V. gallina, V. Pennantii, V. rugosa. — Brit. 



co. generally. Shores and deep water, C. 



A ST ARTE. 



17. A. triangularis, Mont. — Mactra and Goodallia, minutissima and 



triangularis. — Northern parts of Britain, 15 to 20 fathoms, C. 

 Minute, triangular. 



18. A. elliptica, Brown. — Crassina e., Crassina ovata, and C. sulcata. 



Scotland, 5 to 10 fath., mud, M. C. Oblong, smooth near the 

 margin. 



19. A. sulcata, Costa. — [Pectunculus) V. scotica and Bamnoniensis, 



Crassina sulcata, etc. — Devon, Cornwall, Bantry, etc., C. 

 Thickly ribbed. 



20. A. compressa, Mont. — [Venus) Venus and Crassina Montagui, Cy- 



prina comp. — Scarborough, Northumbria, Bantry Bay, Firth of 

 Forth, 7 to 40 fath., M. C. 



21. A. crebricostata, Forbes. — .Zetland and Skye (dead), K. Eibs 



more numerous than in A. sulcata. 



22. A. arctica, Gray. — [Crassina) Venus borealis, Astarte compressa. — 



Aberdeen, Zetland, St. Andrew's bay, etc., Rr. Lenticular, not 

 ribbed. 



Cytherea. 



23. C. chione, Linn. — [Venus.) — Plymouth, S. Devon, Falmouth, 



Carnarvon, 12 to 20 fath., Mr. 



