POLYCHAETE WORMS, PART 1 245 



maxillae iv anterior curved plates with 4-9 (left) and 7-11 (right) 

 teeth; maxillae v small chitinous plates, each with a single tooth. 



Key to the New England Subgenera and Species of Onuphis 



1. Branchiae simple, cirriform (subgenus NoTHRi a; fig. 64,c,d) 2 



Branchiae pectiniform or with 2 or more filaments where best developed 



(subgenus Onuphis, fig. 656) 3 



2. Branchiae begin on first setiger (fig. G4c). Parapodia of first setiger not 



greatly enlarged, without heavy acicular hooks. Tube cylindrical, encrusted 



with fine mud O. (Nothria) opalina 



Branchiae begin on setigers 9-13. Parapodia of first setiger greatly enlarged, 

 extending forward and downward beyond the prostomium, with conspicuous 

 amber-colored hooked setae (fig. 65a). Tube free, greatly flattened, with 

 parchmentlike base overlaid with flat rocks, broken shells, etc. 



O. (Nothria) conchylega 



3. Branchiae begin on first setiger as a simple filament (fig. 65c), with a maximum 



of 5-7 pectiniform filaments O. (Onuphis) eremita 



Branchiae begiii on setigers 5-6 as simple or pectiniform filaments, with 

 maximum of 4-5 filaments (fig. 656) . . . . O. (Onuphis) quadricuspis 



Onuphis {Nothria) opalina (Verrill, 1873b) 



Figure 64 



Nothria opalina Verrill, 1873b, p. 102; 1874b, p. 381, pi. 4, fig. 4.— Verrill, in 

 Smith, Harger, and Verrill, 1874, p. 41, pi. 7, fig. 4. — Hartman, 1944a, p. 

 340, pi. 17, fig. 19. 



Onuphis cf. holobranchia Mcintosh, 1903, p. 152, pi. 13, figs. 38-39. — Not Maren- 

 zeller, 1879. 



Onuphis cf. opalina Augener, 1906, p. 137, pi. 4, figs. 74, 75. 



Description. — Length up to 125 mm., width up to 4 mm., segments 

 numerous. Prostomium (fig. 64, a, 6) vvdthout eyes. Ceratophores 

 of occipital antennae long, ringed (8-11 rings). Dorsolateral pah" of 

 occipital antennae longer than the median unpaired one. Branchiae 

 (fig. 64,c,(i) simple, long, slender, beginning on first setiger and 

 continuing to near posterior end. Ventral cirri subulate on fii'st 6 

 setigers. Special hooked setae of anterior 5 setigers tridentate (may 

 be worn). Anal cirri 4, moderately long. Color, in alcohol: pale 

 yellowish white with brilliant opalescent lustre. Tube: thin inner 

 parchmentlike lining to which is cemented a thin to thick covering 

 of fine mud, forming a long, slender, cylindrical mud tube. 



Biology. — Dredged on bottoms of mud, ooze, and mud with sand 

 or gravel. Found in the stomach of haddock (Georges Bank, 1953, 

 1954, 1955, E. Wigley). 



Material examined. — Numerous specimens from Gulf of St. 

 Lawrence (south of Anticosti Island), Nova Scotia to oft' Chesapeake 

 Bay, Albatross stations, in 14 to 1,255 fathoms. 



Distribution.- — ^Gulf of St. Lawrence to off Chesapeake Bay, 

 West Indies. In 14 to 1,255 fathoms. 



