47 



legs of normal appearance, 5-articulate, and tipped with one or 2 slender claws. 

 Posterior legs rather unlike the anterior, though composed of the same number 

 of joints, last joint very small, and provided with 3 more or less unequal setae, 

 one of which is generally pectinated; none of the setae recurved. Caudal 

 rami well developed, but of somewhat different shape in the several genera; 

 in all of them, however, a very conspicuous triangular unpair prominence 

 occurs just behind their base, tipped with a thickish densely hairy seta. Ovaria 

 and testicles extending between the lamellae of the valves behind. Ejaculatory 

 tubes comparatively simple, wholly wanting the whorls of radiating spikes 

 found in other Cyprids; eferent ducts not convoluted. 



Remarks. The most characteristic feature of the present subfamily is 

 perhaps the comparatively simple structure of the ejaculatory tubes in the male. 

 Another character, which this subfamily shares with the next one, the Macro- 

 cy prince, may also here be named, viz., the sub-pediform structure of the palps 

 of the maxillipeds in the female. An attempt to a similar structure is however 

 also found in one of the genera belonging to the typical Cypridae, viz., 

 Ilyocypris. Nor can the want of vibratory plates on these limbs be regarded 

 as a decisive character, as these plates in some of the typical Cypridae (Cy- 

 pridopsis, Potamocypris) are found to be nearly quite obsolete. In all other 

 respects the Cyprid type is pretty well manifested, and the present group 

 cannot therefore be considered to be so decidedly different from the other 

 Cypridae as suggested by G. W. Mtiller. 



3 genera referable to this subfamily will be treated of in the succeeding 

 pages, and a 4th genus, Pontocypria, has also been added by G. W. Muller. 



Gen. 1. Pontocypris, G. O. Sars, 1865. 



Generic Characters. Shell comparatively thin and pellucid, of a more or 

 less trigonal shape, with the valves unarmed on the edges, but rather densely 

 hairy. Eye well developed. Both pairs of antennae slender and distinctly 

 natatory; the anterior ones with the first 2 segments of the basal part 

 imperfectly defined, terminal part distinctly 5-articulate and clothed with rather 

 long setae. Posterior antennae with the first 2 joints of the terminal part long 

 and narrow, penultimate joint, on the other hand, quite short and, as usual, 

 produced at the end anteriorly to a claw-bearing prominence, last joint so very 

 minute, as easily to escape attention, though armed in the usual manner; 

 sensory appendage of 1st joint comparatively large, club-shaped, its extremity 

 being bladder-like dilated; natatory setae of same joint well developed; apical 



