14 G. O. Sars. 



power, it may, however, easily be seen, that these appendages 

 more properly issue from a separate, but extremely small 

 terminal joint, at the base of which there is a small thumb- 

 like prominence (see fig. 16). 



Between the posterior legs and the insertion of the 

 caudal rami there is a rather long interspace, which is 

 occupied by the genital lobes. These, in the female, are 

 simple, rounded, whereas in the male they carry the greatly 

 developed copulative organs (see fig. 4). The latter have 

 the character of 2 very large and perfectly symmetrical 

 pieces, of a somewhat irregular oblong oval form, and 

 attached to the body by a comparatively narrow flexible 

 stalk. They admit of being wholly extruded from the 

 shell, and during copulation they are introduced within the 

 shell-cavity of the female, applying themselves firmly to 

 the genital lobes of the latter. When at rest, they extend 

 horizontally along the sides of the abdominal portion of the 

 body, partly concealing the bases of the caudal rami (see 

 fig. 4), their anterior parts being ventrally in immediate 

 contact with each other (conf. fig. 18). The outer face of 

 the pieces is perfectly smooth throughout, whereas the inner 

 face appears very uneven, exhibiting in the anterior half 

 several strong, irregularly curved chitinous stripes partly 

 projecting into more or less distinct processes, one of which 

 is rather prominent and claw-shaped. Between the stripes 

 the flexuous spermatic duct may be traced, opening out, it 

 would seem, at the base of the above-named claw-shaped 

 process. Behind, each piece is continued into a thin triangu- 

 lar plate, well defined inside from the more compact an- 

 terior part, and forming at the base a projecting angle. 

 The form of these terminal lamellæ is very different from 

 that found in other male Cyprididæ. 



