104 THE MOLLUSCA OF THE FIRTH OF CLYDE. 
FAMILY PLEUROBRANCHIDH, Forbes and Hanley. 
PLEUROBRANCHUS, Cuvier. 
Pleurobranchus plumula, Montagu. 
Bulla plumula, Montagu. 
Habitat—Under stones at lowest ebb of spring tides at 
Farland Point, Cumbrae; scarce. Mr. Robertson has found 
it not unfrequent in similar situations, and down to 15 
fathoms—the specimens from the latter depth being from 
fishermen’s lines. Messrs. Greville and Miles found a Pleuro- 
branchus at Holy Island, Lamlash; probably referable to the 
present species. 
British distribution.—Throughout many parts of our 
coasts, but local. It appears scarcer on the east coast, not 
having been found by Dr. M‘Intosh at St. Andrews, nor by 
Mr. Alder; it is, however, recorded by Dr. Johnston from 
Holy Island, near Berwick. 
Foreign localities.—Mx. Jeffreys states that it ranges from 
Sweden, throughout France, the Mediterranean, Adriatic, 
and Aigean Seas. 
Famity RUNCINIDA, Gray. 
Runcina, Forbes. 
Runcina Hancocki, Forbes. 
Habitat—Rock pools, Farland Point, Cumbrae, in com- 
pany with the Limapontia (Vorman). 
ORDER NUDIBRANCHIATA, Cuvier. 
(SUB-ORDER PELLIBRANCHIATA. ) 
FamILy LimapontiiD2&, Alder and Hancock. 
Limaponttia, Johnston. 
Limapontia nigra, Johnston. 
Habitat.—In rock pools at Farland Point, Cumbrae ; 
d 
abundant (Norman). I have not noticed either this or the 
preceding species. 
Famity Enysip#&, Alder and Hancock. 
ExysiA, Risso. 
Elysia viridis, Montagu. 
Habitat—In rock pools on the coasts of Bute and Cum- 
brae (A. Brown); common on all the coast (Norman). 
