353 BOPYRID^. 



narrowed so as to resemble a shield, and embedded in the 

 first segment of the body. Its anterior margin is dilated 

 over the base of the antennae, the extremities of which 

 extend beyond it. The inner pair of antennae are 

 minute and rudimental ; the outer pair are larger, and 

 composed of five joints, gradually attenuated, and ter- 

 minated by a small articulated flagellum. The mouth is 

 covered by a pair of lamellated foot-jaws, somewhat re- 

 sembling those of the genus Cymothoa, and the mandibles 

 are arranged as in the same group ; but, as described by 

 M. Edwards, they are more slender towards the tip, and 

 are destitute of any articulated appendage. The other 

 parts of the mouth appear to be replaced by semi-mem- 

 branous lobes, of which the precise structure has not yet 

 been determined. The segments of the body are dis- 

 tinct, with the lateral margins sub-continuous, but desti- 

 tute of epimerae, thus disagreeing with the Cymothoa. 

 The legs resemble those of the male ; each of the six 

 anterior pairs are furnished beneath at the base with two 

 appendages of considerable size, one being broad, folia- 

 ceous, of a semi-corneous consistence, and folded beneath 

 the body so as to assist in forming a large ovigerous 

 pouch, covering the whole of the underside of the body ; 

 the other being an elongated slender membranous fila- 

 ment, which lies on the outside of the body, floating in 

 the water, and resembling the branchiae attached to the 

 legs of the Amphipoda. The tail is small and ovate, with 

 the segments indistinct, except at the sides, where they 

 are marked by slight incisions ; the appendages attached 

 to the five anterior segments are elongate, and branched 

 like a piece of coral, whilst the posterior pair are slender, 

 cylindrical, and simple. Several of the basal appendages 

 are, moreover, furnished at the base beneath with a small 

 scale, lying beneath the tail. 



