NO. 2 HARTMAN : NEW SPECIES OF POLYCHAETOUS ANNELIDS 163 



the second segment, though with increasing number of hooks and fewer 

 setae; posterior to the twenty-eighth segment the ventralmost setae are 

 absent. 



Family Disomidae 



The family DISOMIDAE has not heretofore been reported from 

 the Western Hemisphere or the eastern Pacific. It is a small family; its 

 affinities are with the Spionidae and Chaetopteridae, but it differs from 

 these in having a setigerous cephalic cage, and in its parapodial struc- 

 tures. It is known through only 2 genera, Disomides Chamberlin 

 {■=Disoma Oersted) and Poecilochaetus Claparede. 



Three species of Poecilochaetus have been described, one since the 

 excellent studies by Allen (1904, pp. 79-151) on the anatomy of this 

 group. These species are: 



Poecilochaetus fulgoris Claparede (1874, p. 9), dredged from the 

 eastern Atlantic, off western France, in 725 fms. 



Poecilochaetus serpens Allen (1904, p. 79), from northwestern and 

 southern Europe. 



Poecilochaetus tropicus Okuda (1937, p. 294), from the South Sea 

 Islands. 



Another member of this genus, Poecilochaetus johnsoni, new species, 

 has recently been discovered in southern California, near the mouth of 

 Mission Bay. 



Genus POECILOCHAETUS Claparede 



Prostomium small, subglobular, with 4 eye spots, with an antero- 

 ventrally inserted median antenna, and a trifid nuchal organ. Two ex- 

 tensile, elongate palpi, grooved as in the Spionidae. First segment setig- 

 erous, robust, directed anteriorly at sides of prostomium, provided with 

 stout setae that form a cephalic cage (pi. 30, fig. 17), its ventral cirrus 

 greatly enlarged (pi. 30, fig. 18). 



Parapodia between segments 7 and 11 have dorsal and ventral cirri 

 that are clavate, with bulbous tips (pi. 30, fig. 16) ; more posteriorly 

 dorsal and ventral cirri are flattened, foliose (pi. 30, fig. 14). Setae 

 include plumose (pi. 30, fig. 22), pointed serrulate (pi. 30, fig. 21), 

 falcate crotchets (pi. 30, fig. 19), and blunt acicular with a bushy 

 tip (pi. 30, fig. 24). 



