390 MARSHALL: ADDITIONS TO “‘ BRITISH CONCHOLOGY.” 
T. convexa W. Wood.—A perfect specimen was found by a 
lady, washed ashore on Paignton Sands, and Mr. Cundall 
found another, also perfect, cast ashore in a little bay near 
Barricane, North Devon. Doggerbank, a young specimen 
(Jeffreys); Rum Island, 33 f.; Loch Hourn, 20 f. and 
75 {.; Stornoway Harbour, tof. ; Loch Linnhe, 15% 
(Somerville and J.T.M.); Loch Fyne, 20 f. ; Torbay, 13 f. 
All the above dredging records were of the young only. 
These are triangular in shape, the beaks being more promt 
nent and the dorsal margins more sloping than in the 
adult. Its habitat is well illustrated by an instance in 
which Admiral Bedford, when weighing off Mull, brought 
up six fine living specimens on the flukes of the anchor, 
embedded in a mass of stiff clay. 
This is a typical shell of the Belfast estuarine clays, 
where in some places they occur in great profusion and 
in perfect preservation. A specimen found by Canon 
Grainger is three inches broad. 
T. distorta Mont.—Low water at Torbay and Weymouth. 
Var. truncata Turt.—Torbay; Weymouth. The form of 
this variety is caused by its occupying the deserted burrows 
of Saxicave. 
Fossil in the Belfast deposit ; several large valves, 
ti in. by § in. (Praeger). 
My largest specimens, from Torbay, are an inch in 
breadth. The young do not vary in shape like the adult, 
but are always depressed, subquadrate, and equilateral, 
the beaks central, acute, and prominent. 
Poromya granulata Nyst and W.—Loch Broom, 50 f., a 
small live specimen. 
Nezra abbreviata Forb.—18 to 75 fathoms. Cromarty 
Bay (Dawson); Barra, 53 f. (Somerville)! Loch Linnhe, 
24 f. (Knight)! Southport, a valve in drifted débris 
(Chaster); “Brodick Bay, 4of.;) Kyles of Bute isa 
Loch Alsh, 35 f. ; Aberdeenshire. 
J.C., viit., July 1807 
