374 ACCOUNT OF 



PHOLAS. 



Animal an Ascidia. Shell bivalve, divaricated, 

 with several lesser, differently shaped, accesso- 

 ry pieces at the hinge. Hinge recurved, united 

 by a cartilage. In the inside, beneath the hinge, 

 is an incurved tooth. 



l y crispatus. P. D.M. Lcith Roads, AberladyBay, 



and Dunbar. 



2. candidus. P. D. M. Ditto, ditto. 



3. striatals. D. M. In drifted wood, Dunbar. 



4. dactylus. P. D.M. Various parts of the shores 



of the Frith. 



BIVALVIA. 



Animal an Ascidia. Shell bivalve, generally ga- 

 ping at one end. Hinge with strong, broad, 

 thick teeth, seldom more than one, and not in- 

 serted into the opposite valve. 



3. arenaria. P. D. M. Dunbar, Aberlady Bay, and 



other coasts, common. 



% margaritifera. P. D. M. Loch Tay. From these shells 



valuable pearls are often 

 taken. 



3. inaequivalvis. M. Fine live specimens are ta- 

 ken by the dredge in Leith 

 Roads ; and single dead 

 valves are found on many 

 parts of the coast. 



