FOOD, HABITS, ETC. 85 
dispersal. Not infrequently large Water. Beetles 
have been captured in flight from one piece of water 
to another that have proved to be carrying molluscs 
attached to them. It may be one or more Bivalve 
Shells holding tight on to the legs, or a freshwater 
Limpet (Ancylus) or two, adhering to the wing-cases. 
The fry of other kinds of Snails may be readily 
transported in similar fashion. Water-fowl and 
Wading Birds have likewise been taken with 
Bivalves adhering to their feet, and have been 
observed to fly off with water-weeds clinging to 
them that might well bear both small kinds of shells 
and ova. Young Snails may also be transported 
sticking to the bird’s plumage. On the arrival of 
the insect or bird at a fresh piece of water these in- 
voluntary passengers drop off, and in this way fresh 
colonies are started. 
Land molluscs and their eggs adhering to vegeta- 
tion are carried down by flood waters and stranded 
on subsidence in fresh pastures. Small forms 
dwelling in swampy ground and ova may further- 
more be conveyed to distances in the mud sticking 
to birds’ feet, or clinging to their feathers, especially 
if the birds be such as roost on the ground. 
Transport by man, both intentional and acci- 
dental, hardly enters into consideration here; but it 
is interesting to remark how the commoner and 
hardier European Slugs and Snails have been intro- 
duced near ports of call in many widely separated 
