364 



A HISTORY OF RECENT CRUSTACEA 



spite of tlie projecting uropods and even of the perseon- 

 process, they roll about with great facility. The projections 

 from the body promote their resemblance to the weed 

 among which they live. Campecopea, lineata, Hesse, 

 taken ' under stones, near Brest,' seems to be the same 

 species. 



Cillccpii, Leach, 1818, has the front or median part of 

 the pleon dorsally produced into a long spine in the male, 

 but not in the female. The apex of the pleon is notched 

 as in Gymodoce. 



Cycloidura, Stebbing, 1878 (Gyclura, Stebbing, 1874, 

 preoccupied), has the pleon .wider than the preceding 

 part of the animal, a peculiarity which it shares with very 

 few of the Isopoda. The large oval branches of the 

 uropods are of unusually thin texture, and are very salient^ 

 the movable outer branch folding only partially beneatf"" 

 the fixed inner one. The Australian type-species, Gycli 

 diwra venosa, has the seventh segment of the perceon pf 

 duced into a large dorsal spine, at 1^ 

 in the male. A new genus near to Cydo. ' 

 dura, may be required for the Californian 

 species, SphceroTna a/mplieavda, Stimpson. 

 Isoclddus, Miers, 1876, rather closely 

 resembles the preceding genus, but has 

 the uropods ' subequal, of a slightly sig- 

 moid shape, and acute at the extremity.' 

 The spine of the seventh person-segment 

 is not developed in the female. The 

 species, armatus (Milne-Edwards) and 

 spiniger (Dana), are from New Zealand. 



Ceratocephalus, Woodward, 1877, has 

 the head produced in the male into three 

 large processes of which the central is 

 much the longest. In the female ' faintly 

 Fig. 31. - ceraiocpha- marked projections' take the place of the 

 lus Grayavua Wood- processes. The terminal segment of the 



■ward [HasweU]. '^ . . j j • t.,° i • i. J 



pleon IS produced m an obtusely pointed 

 process beyond the uropods, which are affixed high up on 

 the sides of the segment, and have the outer movable branch 



