400 SPH EROMID!. 
Dana has reduced this family to the rank of a sub-family, 
and has separated Nisea and Campecopea, as a sub-family, 
from the remainder of the genera. 
The species of this family frequent the rocky shores 
of the ocean, amongst Thalassiophyte, or under stones 
and along the muddy banks of estuaries. Others, how- 
ever, are generally found adhering to marine plants 
floating on the surface of the sea, and some exotic 
species eat deeply into water-logged timber, like Limnoria. 
They are able to run and swim with considerable agility, 
and afford a large supply of food to fishes. 
