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HISTORY OF BRITISH CRUSTACEA. 
Lepeophtheirus Thompson^ Baird. — Carapace round) 
in the male rather broader. Abdomen long, the length of 
thorax. Caudal plates short, rather broad. Sternal fork 
with sharp, simple branches. 
Hab. Ireland : on the turbot. 
Gen. 174. CHALXMUS, Burnt. 
Feet as in preceding. Thorax with four distinct seg- 
ments. Frontal plates without sucking-discs, but furnished 
with a long and slender appendage from the centre of fore 
surface. 
Dr. Baird remarks on this curious genus, which Kroyer 
was disposed to think might prove the young of Caligus , 
that the long and slender organ above alluded to ends in a 
“ round expansion like a sucker, by which it fastens itself 
to the body to which it is found attached. The presence 
of this organ would lead us to suppose that this animal 
must lead a much more sedentary life than the rest of the 
Caligidce , and it would appear in this respect to connect it 
with some of the Lerneada , which we shall find to possess 
a somewhat similar organ of prehension.” 
