1888 .] 
Mr D. Alpine on Bivalve Molluscs. 
173 
Monday, Wi March 1888. 
JOHN MUEKAY, Esq., Ph.D., Vice-President, in the Chair. 
The following Communications were read : — 
1. Observations on the Movements of the Entire Detached 
Animal, and of Detached Ciliated Parts of Bivalve 
Molluscs, viz., Gills, Mantle-Lobes, Labial Palps, and 
Foot. By D. M ‘Alpine, P.C.S. Communicated hy W. E. 
Hoyle. (Plates I, II.) 
(Abstract.) 
In the introduction it is pointed out that, although ciliary motion 
lias been observed and noted in the mussel, independent locomotion 
communicated to the gill itself lias not yet been studied, and it is 
pointed out that a sea-mussel when detached is capable of roaming 
about — can float and can sink. 
Dr Aug. A. Gould and Dr Lockwood (American Naturalist, voh 
iv. p. 331) have observed Mytilus edidis to climb the side of a 
glass jar by the aid of its foot and byssus to the extent of three 
inches in a single night. Besides the entire animal, the mantle- 
lobes, gills, labial palps, and foot all exhibit locomotive activity, and 
all of these parts are endowed with cilia, not merely motile, as in 
the organ of Bojanus, but cilia which, when they are attached to the 
mass, cause it to move from point to point. 
Interest attaching to Investigation. — Before entering into dateils, 
it may be remarked that there is a threefold interest attaching to 
an investigation of this sort. There is, first of all, the peculiarity of 
detached portions of an animal, comparatively high in the scale, 
retaining to a certain extent independent vitality, moving about 
and often rotating, as we shall see, in a certain definite manner and 
direction. Such an appearance is always interesting, whether it be 
the detached portion of a hydra or of an earthworm, the wriggling 
tail of a lizard or the amputated leg of a spider, the writhing por- 
tion of an eel or the palpitating locomotive detached heart of a 
frog. 
Then there is a further interest when it is known that this move- 
ment is due, in whole or in part, to the action of ciliu. Indeed, there 
