NO. 3 HARTMAN : ORBINIIDAE, APISTOBRANCHIDAE, PARAONIDAE 315 



segment. Neuropodia of abdominal segments have modified setae that 

 are pseudoarticulate, acicular, sigmoid or slightly curved; their distal 

 ends are uncovered or hooded. 



Key to Species 



1. Modified setae of posterior neuropodia distally pseudoarticulate 

 (pi. 43, fig. 3) A. fragilis 



1. Modified setae otherwise 2 



2. Modified setae with a distal hood (pi. 43, figs. 1, 2) . . 3 



2. Modified setae without a hood 4 



3. Hyaline hoods of setae distally rounded (pi. 43, fig. 2) 

 A. jeffreysii, sensu Cerruti 



3. Hyaline hoods of setae distally pointed (pi. 43, fig. 1) 

 A. fauveli and A. lopezi 



4. Modified setae in part subuluncinate, in part uncinate (pi. 43, 

 fig. 5) A. uschakovi 



4. Modified setae entirely uncinate (pi. 43, fig. 7) .... 5 



5. Modified setae in a series all about equally thick A. suecica 

 5. Modified setae in a series varying from thickest above to slen- 

 derest below A. near suecica 



