BIVALVES. 
37 
cornea, but exhibits greater activity than it 
does. 
We quote a writer in the Zoologist, who gives 
in a few words the performances of this bivalve 
in confinement. 
When I first put them ( 0 . lacustris) into water 
they immediately began to climb the sides of the 
glass. One of them also commenced crawling 
on the under surface of the water. Its foot was 
now spread out very widely, and while preparing 
for its exploit, it was apparently kept near the 
surface by a minute thread fastened to the sides 
of the glass. When it had left the side, its foot 
appeared to be depressed in the middle, so as to 
act as a kind of boat. I shook the tumbler, so 
as to fill the little vessel with water; but to my 
surprise it sunk, not suddenly but gradually, as if 
it were lowering itself by a thread attached to 
the surface of the water. They also appeared to 
give out a quantity of glutinous matter wherever 
they went, so much, that in about half an hour 
seven or eight were entangled and tied together 
by each other’s trailing threads.” 
The capped Cycle inhabits ponds, canals, 
ditches, and lakes in the South and centre of 
England, becoming rare in the North; it is ab¬ 
sent in Scotland, and is rare and local in Ireland, 
having been observed only near Dublin, Dundalk, 
Toughal, and Cork. 
