296 ANNELIDA 



4. LEFRiEA Malmgren. Three pairs of branching gills; setae begin 

 on 4th segment and extend the length of the body: several species, 1 in 

 the Woods Hole region. 



L. rubra Verrill. Body elongate, swollen anteriorly; color bright 

 red; length 5 cm.; width 3 mm.: North Carolina to Vineyard Sound; 

 in tubes on shells, etc., below low-water mark. 



5. Thelepus Leuckart. Two pairs of branching gills; setae begin 

 on the 3rd segment and continue nearly or quite to the hinder end ; eyes 

 numerous: 1 species in the Woods Hole region. 



T. cincinnatus (Fabricius). Setae extend almost to the hinder end 

 of the body; eyes present; length up to 12 cm.; color yellowish or red- 

 dish: coast of Maine to Vineyard Sound; in tubes often covered with 

 shells; Europe. 



6. PoLYCiRRxrs Grube. Blood worms. Very long, slender worms 

 with bright-red blood; no branching gills: several species, 2 in the Woods 

 Hole region. 



P. eximius (Leidy). Body bright red with about 100 segments, of 

 which 25 bear setae: North Carolina to Cape Cod; in sand and mud in 

 shallow water; veiy common. 



P. phosphoreus Verrill. Brilliantly phosphorescent worms when 

 disturbed; length 8 cm.; first 24 segments bear setae: Long Island 

 Sound to Bay of Fundy. 



7. Enoplobranchus Verrill. Blood worms. Body flattened; setae 

 extending to the hinder end of the body; with branched parapodia in 

 the middle division : 1 species. 



E. sanguineus (Verr.). Body very long and slender; branched para- 

 podia begin on segment 12; color bright red; length 35 cm.; width 7 

 mm.: Virginia to Gulf of St. Lawrence; common at low-water mark; in 

 mud and sand. 



Family 3. AMPHARETIDAE. 



Similar to the previous family; a bundle of setae present on each 

 side of the head in front of the gills; tentacular filaments small and not 

 numerous; no branched gills, but 4 pairs of filamentous ones present: 

 several genera. 



Ampharete Malmgren. Tentacular filaments few in number; 

 gills on 3rd and 4th segments: numerous species, 2 in Woods Hole 

 region. 



A. setosa Verrill. Body thick anteriorly, tapering backwards; 40 

 tentacular filaments; color light green or red; length 20 mm.; width 3 

 mm.: Long Island and Vineyard Sounds; in rough tubes in shallow 

 water. 



