40) THE MOLLUSCA OF THE FIRTH OF CLYDE. 
Thracia pubescens, Pulteney. 
Mya pubescens, Pulteney; Anatina myalis, Lamarck. 
Habitat.—Mr. Robertson has a single valve of this species, 
fresh and adult, taken by him in Campbeltown Loch, where, 
however, it may have been deposited by some far-travelled 
codfish—(no ships discharge ballast in that inlet). The shell 
appears in the lists of Mr. Smith (of Jordanhill) and the Rey. 
Dr. Landsborough as an inhabitant of our waters, but until 
Mr. Robertson’s “find” no corroboration of its presence so 
far north had been received. 
British distribution—Very scarce, and probably con- 
fined in a living state to the Devonshire and Cornish 
coasts. 
Foreign localities—Atlantie coast of France (Macé and 
others), Spain, Portugal, and Canaries (‘A ndrew)—Canaries 
being doubtful, and only single valves obtained— Aigean 
(Forbes). 
Thracia disterta, Montagu. 
Mya distorta, Montagu; Venus sinuosa, Pennant ; Amphi- 
desma distortum and A, truncatum, Pleming. 
Habitat—Amongst nullipore and dead shells, in 8 to 25 
fathoms; by no means scarce, but rather local. It is common 
on the south end of Bute, off St. Ninian’s Bay and Garroch 
Head ; as well as on the western edge of the Tan Spit, Cum- 
brae. I have taken it also off Craigmore and Ascog in Bute; 
and Silvercraigs, Loch Fyne. The specimens were invariably 
free, but were nevertheless frequently much distorted. 
British distribution.—Locally but widely diffused through- 
out our seas. It appears usually to frequent the abandoned 
burrows of the boring mollusca, and crevices in rocks; a habit 
which I have not observed in this district. 
Foreign localities—Norway (Lovén and others), northern 
and western France (De Gerville and others), Mediterranean 
(Deshayes). 
FAMILY CoRBULIDA, Fleming. 
NERA, Gray. 
Nera abbreviata, Forbes. 
Nera vitrea, Lovén. 
Habitat.—In Loch Fyne this species was taken on a 
muddy bottom, in about 40 fathoms, by Messrs. Barlee and 
