SMART AND COOKE : MARINE SHELLS OF SCILLY. 289 



Mytiius edulis L. — In the crevices of the outer rocks all round 



the islands, but scarcely common, and always solitary and 



small. 

 M. modiolus L. — Occasionally thrown up. 

 M. barbatus L. — Dredged outside Menavawr, frequently 



attached to sea weeds, but always very small specimens. 

 M. Adriaticus Lam. — Dredged off Menavawr, in a nest or 



case ; also occasionally thrown ashore dead. 

 Modiolaria marmorata Forbes. — A few single valves. 

 M. costulata Risso. — Trawl refuse and dredged, always 



attached to seaweeds, with M. barbatus. 

 Crenel la rhombea Berk. — Single valves dredged in forty 



fathoms sand, but rare and local. 

 Nucula nucleus L. — Not rare in the gravel from outside 



dredgings. 

 Pectunculus Glycimeris L. — Small specimens common, 



especially in forty-fathom dredgings on stony ground ; 



large specinens very scarce, but occasionally thrown up. 

 Area lactea L. — Occasionally met with in forty-fathom 



dredgings. 

 Area tetragona Poll. — Very large single valves, over 1-25 in. 



broad, occasionally thrown up ; small single valves abun- 

 dant, with A. lactea, and far more common. Sometimes 



obtained alive when large stones are brought up by the 



dredge. 

 Montacuta bidentata Mont. — Dredged in 8 fms., fine sand, 



Crow Sound, common. 

 M. ferruginosa Mont. — With M. bideiitata, and equally 



abundant. 

 Lasea rubra Mont. — Golden BaU bar: would probably be 



found commonly if properly searched for. 

 L, rubra var. pallida Mont. — Rocks under Cromwell's 



Castle. 

 Kellia suborbicularis Mont. — Dredged in 40 fms., and 



u 



