POLYCHAETE WORMS, PART 1 207 



As used herein, Sphaerodorum includes Ephesia gracilis Rathke 

 {=Sphaerodorum flavum Oersted, Pollicita peripatus Johnston, Sphae- 

 rodorum papillijer IMoore). Setae simple. Dorsal glandular capsules 

 two (as in type) or more per segment. 

 Contains only one New England species. 



Sphaerodorum gracilis (Rathke, 1813) 



Figure 52,a-c 



Ephesia gracilis Webster and Benedict, 1887, p. 728. — Southern, 1914, p. 88. — 

 Fauvel, 1923, p. 377, fig. 148,a-/.— Uschakov, 1955, p. 220, fig. 70.— Petti- 

 bone, 1956a, p. 559.— Clark, 1960, p. 21.— Day, 1960, p. 326. 



Sphaerodorum gracile Eliason, 1962, p. 247. 



Description.^ — Length up to 60 mm., width up to 1 mm., segments 

 up to 120. Body elongate, slender, flattened ventrally, strongly 

 arched dorsally, widest near anterior end, tapering slightly anteriorly 

 and more so posteriorly. Eyes four, under integument (may be some 

 additional spots). Integument covered with minute papillae dorsally 

 and ventrall}^. Spherical glandular capsules present in two dorsolat- 

 eral longitudinal rows above parapodia (fig. 52,a,b); capsules with 

 short papilliform process. Parapodia short, conical, covered with 

 cylindroconical papillae, one near the distal tip being larger and 

 forming a postsetal lip (sometimes referred to as ventral cirrus). 

 Setae few in number (4-6), simple, short, with tip curved (fig. 52c). 

 Aciculum colorless. 



Color: pale yellow to brownish yellow with capsules opaque 

 yellowish white, eyes deep brown. Females may be filled with large 

 oval eggs with thick shell; shell is striated, irregularly thickened, 

 appearing as polygonal areas (specimens from Greenland). Eggs 

 dark red with purphsh tinge (Webster and Benedict). 



Biology.— Found at low water in coralhne algal region, in fissures 

 of rocks. Dredged on bottoms of fine sand, mud, sandy mud, rocks, 

 with shells, hydroids, sponges. It is able to crawl slowly and may 

 twist in screwlike coils (Mcintosh). Taken in surface tow at night 

 in Ireland (Southern). Found in the stomach of haddock (Georges 

 Bank, 1954, R. Wigley). 



Material examined.— Gulf of St. Lawrence (Bay of Chaleurs, 

 south of Anticosti Island, 15-80 fathoms), off Nova Scotia (US Fish 

 Commission Location 164, 42°36' N., 70°27' W., 75 fathoms, 1878), 

 Massachusetts (Georges Bank, 62-182 fathoms; Location 32-33, 

 off Salem, 90 fathoms, 1877; Location 1038, off Martha's Vineyard, 

 39°58' N., 70°06' W., 146|fathonis, 1881). 



Distribution.- — ^ Widely distributed in the Arctic; also Iceland, 

 Norwegian Coast to North Sea, France, Mediterranean, Labrador to 

 Massachusetts, Bering Sea to southern CaUfornia, north Japan Sea, 

 Antarctic, South Africa. Low water to 723 fathoms; surface waters. 



