FAMILY SYLLIDAE 

 Key to genera and species 



1 Ventral cirri distinct. Palps either separate or fused. Pharynx 



straight, seldom coiled 2 



1' Ventral cirri completely fused to setigerous lobes and in- 

 distinguishable. Palps completely fused. Pharynx long and 

 coiled. (Subfamily Autolytiime) 23 



2 Palps quite .separate. Always two pairs of tentacular cirri. 



Antennae and dorsal cirri articulated. (Subfamily Sylliitae) 3 



2' Palps fused basally. One or two pairs of tentacular cirri. 

 Antennae and dorsal cirri seldom articulated (Subfamily 

 EiiKyUiiiae) 11 



2" Palps fused for more than half their length. One or two pairs 

 of tentacular cirri. Antennae and dorsal cirri not articulated 

 and often small (Subfamily E.vogoiiiiiae) 16 



3 Margin of phai-ynx with a circle of chitinous teeth (trepan) 



and a small dorsal tooth as well. Body flattened (Trypcuio- 

 sijllis). [Trepan with 10 teeth. Blades of setae bidentate. 



Never more than one se.xual .stolon] T. zebra 



3' Margin of pharynx with a single anterior dorsal tooth {Sulli^) 4 



4 Setae of anterior feet compound but setae of middle feet may 



lose their blades and appear simple 5 



4' All setae simple (subgenus Huplosylli.^). [Setae .shaped like 

 boathooks with a boss preceding the curved and bifid tip. 

 Dorsal cirri with 20-30 joints] S. (H.J spongicola 



5 Setae of middle segments reduced to two large simple setae 



with bluntly Y-shaped ends. [Dorsal cirri fusiform with about 



10 joints] S. gracilis 



5' Setae of middle segments fairly numerous and normally com- 

 pound 6 



6 Two or three superior setae of middle segments with very 



long tapered blades; inferior setae with much shorter fal- 



cigerous blades (subgenus Laugcrhausia) 7 



6' All .setae of middle segments with falcigerous blades graded 



in length (subgenus Typosyllis) 8 



7 Dorsal cirri of posterior feet smooth or indistinctly articulated. 



Blades of posterior setae with secondary tooth stouter than 



apical one S. (L.)ferrugina 



T Dorsal cirri of posterior feet distinctly articulated. Blades of 



posterior setae with secondary tooth finer than apical one S. (L.) cornuta 



26 



