82 
.BULLETIN OF THE NATURAL HISTORY SOCIETY. 
attaches itself by its strong byssus, or “beard” of threads. Those torn; 
from their hold in the tide-pools, bring away a large mass of gravel 
with them. Their mode of life may be well studied in the tide-pools 
about Passamaquoddy Bay, where they may be seen under the clear 
water with their posterior ends just above the bottom, gaping widely 
open. The shells bear many growths, both animal and vegetable, the 
most important of which are the great Laminarice, or “ Devil’s Aprons,” 
our largest sea- weeds. In storms these often drag their anchors, and the 
Mussels are thrown up with them on the beaches. 
Economics. The Horse-Mussel is used for food in Eng- 
land, though to no great extent and only locally. Mr. Willis 
says in his time it was never exposed for sale in the markets of 
Halifax, and this seems to be true at present. The fisher- 
men eat it very rarely, if at all, unless pressed by necessity. 
Some of them believe that the byssus or “ beard,” and probably 
the foot from which it springs, are poisonous. The writer has- 
been told of two fishermen, who, storm-stayed at the Wolves, 
ran short of provisions. They ate Horse-Mussels and one of 
them died a few hours later. If his death really was caused 
by the Mussels, it is altogether probable that the byssus and 
foot really are the poisonous parts, and until we have further 
information on the subject, they had better be removed 
before the animal is eaten. 
This species is also very good bait, and is said to be exten- 
sively used for that purpose in Newfoundland. But it is so 
much harder to obtain than Mytilus edulis (every specimen 
must be torn up by main force, unless carried up by Lamin- 
arice) and so much less common and less accessible, that it is- 
never likely to be of very much value. 
The shells are usually very beautiful within, having often 
a delicate pearly lustre. They ought to be available for many 
ornamental objects, such as trays for trinkets, and the 
like. Occasionally pearls of poor lustre are found in them,, 
but we have not heard of any of value. 
In Europe it has been used to some extent to bind 
together the shifting materials of breakwaters on sea coasts. 
The tough threads of the byssus bind together everything 
within reach and a coating of these animals forms a strong 
and elastic buffer against the force of the waves. 
