NO. 3 HARTMAN: ORBINIIDAE, APISTOBRANCHIDAE, PARAONIDAE 255 



1. Only the first segment without parapodia; body more than 20 

 mm long when adult ; proboscis epithelial and eversible . 



ORBINIINAE 2 



2. Prostomium rounded or truncate (pi. 38, fig. 1 ) at its anterior 

 margin Naineris 



2. Prostomium more or less acutely pointed at its anterior mar- 

 gin when mature 3 



3. All thoracic parapodia provided with only slender, pointed 

 setae Haploscoloplos 



3. Some thoracic neuropodia with setae of another kind . . 4 



4. Thoracic neuropodia of two abruptly different kinds . . 5 



4. Thoracic neuropodia not abruptly different .... 6 



5. Anterior three thoracic neuropodia different from those 

 farther back and provided with bristle-tipped setae (pi. 42, 

 fig. 2) Califia 



5. Posterior thoracic neuropodia with thick, modified spines as- 

 sociated with a glandular pouch Phylo 



6. Abdominal neuropodia with flail setae (abruptly bent near 

 the distal end) ; neuropodial ridges foliaceous . Scolaricia 



6. Flail setae absent 7 



7. Some thoracic segments with rows of fringe along the ventrum 

 and sometimes on parapodial postsetal ridges . . Orbinia 



7. Without rows of fringe on the ventrum 8 



8. Abdominal neuropodia, especially in median and posterior 

 segments, with thick acicula, occurring singly in a ramus and 

 projecting from the parapodial lobe (pi. 32, fig. 2) ; branchiae 

 usually first present from about the fifth or sixth segment 

 Scoloplos (Leodamas) 



8. Without such thick acicula projecting from abdominal neuro- 

 podia; branchiae usually not present before about the tenth 

 segment Scoloplos (Scoloplos) 



9. Branchiae absent Orbiniella 



9. Branchiae present on some segments 10 



10. Some thoracic neuropodia with uncini and subuluncini . 



Protoaricia 



10. Some neuropodia with geniculate setae with rostrate tip 

 (swan-shaped setae) Proscoloplos 



