294. BOPYRIDA. 
whereas Gyge is only so at the anterior portion of the 
animal. 
It also differs in the more rudimentary condition of 
both pairs of antenne, and in the larger development of 
the ovigerous plates. 
The maleis in proportion much larger, being nearly one- 
half the length of the female. It has also the cephalon 
proportionately larger, and the antenne, particularly those 
of the second pair, largely developed. The segments of 
the pleon are distinct, anteriorly being nearly as large as 
those of the pereion, and decreasing in length and breadth 
posteriorly very rapidly ; whereas in Bopyrus they are 
fused together except at the margins, smaller than those 
of the pereion, and decrease gradually. 
The larve of this genus appear to correspond very 
closely with those of Bopyrus, but appear to have the 
antenne laterally nearer to one another. 
