CRUSTACEA SYSTEMATIC REVIEW 



295 



Cymothoidea, hermaphrodite, some living free, others parasitic on fishes : Cymothoa, 

 Anilocra, Cirolana, Nerodla, Aega, almost exclusively marine forms. Sphceromidm, 

 free living, mostly marine, Spharoma. Pranizidce, free in the sea, the 3 anterior 



FIG. 198. Caprella acutifrons, after 

 P. Mayer. A, male from the side ; B, from 

 the back. 01, Anterior, a 2 , posterior an- 

 tenna ; &2> &3, &6> & 7 & 8. 2(i to 8tn thoracic 

 feet, the 2<1 moved on to the throat; br, 

 gills in the place of the 4th and 5th thor- 

 acic feet; cth+I+II; cephalo-thorax = head 

 +lst and 2d thoracic segments ; 1 1 1- VI II, 

 free thoracic segments; ab, truncated 

 abdomen. 



FIG. 199. Diastylis stygia, male (after 

 G. O. Sars). aj, Anterior, a^, posterior 

 antenna; cth, cephalo-thoracic shield ; IV- 

 VIII, free thoracic segments ; abi-abj, ab- 

 dominal segments ; PI, 1st pleopod ; p fi , 6th 

 pleopod ; en, endopodite ; ex, exopodite. 



thoracic segments fused with the head. Anceidce, female parasitic, male free-living, 

 Anceus. Idotheidce, free living, principally marine, Idothea. Asellidcc : Aselhis, 

 fresh water. Oniscidce, on land : Oniscus, Porcellio. The divisions of the Bopyridce. 



