THE MOLLUSCA. 125 



Anomia ephippium. Occasionally found upon Modiola modiolus. 

 This curious mollusk is attached to shells, rocks, and 

 stones by a muscle projected through an orifice in the 

 lower valve, near the hinge ; it is a lustrous, pearly shell, 

 and adapts itself to the shape of the body to which it is 

 attached. 



Anomia patellaformis. Anomia aculeata. Like the ephippium, 

 these two latter have been found on Modiola modiolus. 



UNIVALVES. 

 GASTEROPODA NUDIBRA NCHIA TA . 



EOLIDID^E. 

 CEolis coronata. 

 (Eolis papillosa. 



DOR1DID.&. 



Doris Johnstoni. 



The Nudibranchiata are the naked mollusks or sea-slugs. 

 They are curious, and some of them beautiful animals. We 

 owe their presence to the construction of the Pier, as they 

 are found on its timbers and on the stones heaped round 

 their foundations. 



GASTEROPODA PR OSOBRA NCHIA TA . 

 PATELLID^E. 



Patella vulgata (Common Limpet). Rare, and when found 



very much worn. 

 Patella athletica. Like the above, very rare. 



DENTALIAD^E. 



Dentalium entalis (Tooth Shell). Some years ago this was a 

 common shell, but now is only occasionally found, and 



