303 



in reality differs very materially both from Enhydrosoma and from the other genera 

 included in the present family. 



200. Rhizothrix CUrvata, Brady & Robertson. 



(PI. CCVIH). 

 Rhizothrix curvata, Brady & Eobertson in Brit. Assoc. Report 1875, p. 197. 



Syn: Enhydrosoma curvatum, Brady. 



Specific Characters. Female. Body comparatively robust, more or less 

 curved, maggot-shaped, slightly attenuated behind, with the segments rounded off 

 laterally and crowded closely together. Cephalic segment large and tumid, exceed- 

 ing in length the 3 succeeding segments combined, rostrum replaced by 2 small 

 juxtaposed nodiform prominences. Last pedigerous segment fully as large as the 

 preceding one. Urosome a little narrower than the anterior division, and much 

 shorter, last segment very small, with the anal opercle almost obsolete. Caudal 

 rami arising close together from a broad base, being rounded oval in outline and 

 somewhat divergent, lateral and dorsal setse issuing near the end, middle apical 

 seta about half the length of the urosome. Anterior antennae short and stout, 

 scarcely more than half as long as the cephalic segment, and consisting of only 

 4 joints gradually diminishing in size, 2 or 3 of the setae attached to the 2nd 

 joint remarkably strong and edged with long cilia. Posterior antennae moderately 

 strong, terminal joint not attaining the length of the basal one, and having the 

 apical appendages unusually short, outer ramus armed at the tip with a stout 

 curved seta, coarsely spinulose on the one edge, and with a thin lateral bristle. 

 1st pair of legs very small, with both rami narrow and not very unequal in length, 

 each carrying on the tip 2 slender setse terminating in a tuft of fine spreading 

 cilia, outer ramus a little longer than the inner, with the 1st joint equalling 

 in length the other 2 combined, and armed at the end outside with a long de- 

 flexed spine coarsely ciliated on the outer edge; middle and terminal joints with- 

 out any spines. The 3 succeeding pairs of equal structure, outer ramus without 

 any setse inside, spines of outer edge gradually increasing in length and coarsely 

 spinulose outside; inner ramus very short, with 3 unequal setae at the tip. Last 

 pair of legs with the distal joint comparatively small and obovate in form, mar- 

 ginal setse 5 in number, some of them very small; inner expansion of proximal 

 joint forming together with that of the other side a broad plate, slightly incised 

 in the middle, and carrying on each side of the incision a dense row of 5 ciliated 

 setse, the 3 innermost ones somewhat longer than the 2 outermost. Ovisac com- 

 paratively small, rounded oval in form. 



