THE ECONOMIC MOLLUSCA OF ACADIA. 
15 
given to poultry. From the Squids a kind of oil can be made, 
though we believe it has little value commercially. 
Of the indirectly useful Molluscs, doubtless the most 
important to man, are those which serve as food for the food- 
fishes. A list of the Molluscs known to inhabit New England 
waters, which are eaten by Cod, Haddock and other large fish, 
is given in the “ History of Useful Aquatic Animals of the 
United States, ” pp. 693, 694 and 703. The majority of the 
forms there mentioned occur in the waters of Acadia. It may 
not be amiss to state here, that the stomachs of fishes are fine 
hunting-ground for the conchologist, many species being 
found in them, which are rare, or inaccessible in other ways. 
Indirectly also those Molluscs are beneficial to man, which, 
by forming great tough beds, as the Edible Mussels do, protect 
easily eroded sea-coasts from being washed away ; which bore 
into and ultimately remove reefs and wrecks which are a bar 
to safe navigation, as does the Teredo and its allies; and those 
which are beneficial to the oyster industries, the most import- 
ant of which is the Periwinkle ( Littorina litorea), and some 
others. 
Among the injurious Mollusca, the Ship-worms must take 
first place. Species of Teredo are found all over the world, but 
are most destructive in warm waters. They bore into and 
destroy any kind of timber that is under the surface in pure 
salt water. Hence, wharves, ships, buoys, breakwaters, are 
all attacked, and naturalists and engineers have been put to 
their wits’ ends to study their habits and find a remedy. In 
the following pages will be found some account of their 
results. In Acadian waters we have some three or four species; 
they are most troublesome upon the North Shore and Cape 
Breton coast, where the warmer summer temperature affords 
better conditions for the development of the young, than does 
the much colder water of the Atlantic and Bay of Fundv 
shores. Those Molluscs which bore into stone (Pholas and 
allies) have never done any damage upon our shores. 
Among those which may be called indirectly injurious, are 
those which are destructive to oyster-beds. In American 
waters there are a number of these, the chief of which is the 
