256 
HISTORY OR BRITISH CRUSTACEA. 
at one time believed these curious parasites to be young 
soles. 
Bopyrus squillarum, Latr. Shrimp-fixer . — Antennae 
of the male completely concealed beneath the front of the 
head. Body of the female somewhat elongated. Colour 
pale greenish, above glossy ; abdominal membranes dark at 
their edges. 
Common on the carapace of the Shrimp, which is dis- 
figured by the lodgment of this animal distorting the shell. 
This tumour forms a secure asylum for the protection of the 
soft membranous bodies of these parasites. Colonel Mon- 
tagu remarks that the dissimilarity in the sides of the Bo- 
pyrus is occasioned by the unequal pressure they receive 
from the carapace of the Shrimp; this growth is therefore 
not constantly alike, but depends on the side of the carapace 
tenanted by each individual. 
Bopyrus Hippqlytes, Kroyer. — Antenme of the male 
projecting in front of the head ; body of the female oval. 
The late Mr. Thompson of Belfast found this on the 
Hippolyte varians , taken on the coast of Galway. 
