48 U.S. NATIONAL MUSEUM BULLETIN 22 7 



Material examined. — Specimens from off Labrador, Gulf of St. 

 Lawrence, Nova Scotia, Newfoundland, New Brunswick, Maine, New 

 Hampshire, Massachusetts, Long Island Sound, in low water to 120 

 fathoms. 



Distribution.— Widely distributed in the Arctic. Also Iceland, 

 Norway to France, Labrador to Long Island Sound, Bering Sea to 

 central California, Chile, north Japan Sea, off South Africa. In low 

 water to 1,254 fathoms. 



Genus Sigalion (Aiidouin and Milne-Edwards, MS.) Cuvier, 1830 



Type (designated by Hartman, 1959a, p. 118): Sigalion mathildae 

 (Audouin and Milne-Edwards, ms.) Cuvier, 1830. Contains only one 

 New England species. 



Sigalion arenicola Verrill, 1879 



Figure ll,a,6 

 Sigalion arenicola Verrill, 1879, p. 167; 1881, pp. 319, 320, pi. 7, fig. 5.— Webster 

 and Benedict, 1884, p. 701. — Sumner, Osburn, and Cole, 1913, p. 619. — 

 Hartman, 1942b, p. 34, fig. 44.— Miner, 1950, p. 311, pi. 101. 



Description.- — Length up to 300 mm., width including setae up to 

 8 mm., segments up to 300. Body elongated, squarish in cross sec- 

 tion, tapered posteriorly. One of the paired anal cirri often very 

 long and threadlike, the other short. Elytra numerous pairs, on all 

 segments from segment 27 on, large, thin, transparent, subrectangu- 

 lar, smooth, without tubercles, with 8-13 pinnately branched 

 papillae on lateral margin (2-8 pinnae on each side plus a few short 

 iBlaments along the base; fig. 116). Prostomium subpentagonal, 

 with 4 small eyes arranged in rectangle near middle, with 2 small 

 lateral antennae on anterior side, without median antenna. Para- 

 podial lobes of tentacular segment project anteriorly, lateral and 

 dorsal to bases of the long slender palps, fused to anterior side of 

 prostomium, with 2 pairs subequal tentacular cirri and numerous 

 setae. 



A small pair of dorsal cirri on segment 3. Cirriform branchiae on 

 all segments beginning with segment 5; with 3 parapodial ctenidia 

 above the notopodium. Biramous parapodia with lobes well sepa- 

 rated; notopodium club shaped, with single digitiform process or 

 stylode on dorsoanterior side; neuropodium somewhat bilobed, upper 

 part (with aciculum) longer, with 2 short rounded stylodes on pos- 

 terior side of neuropodium (the upper one longer, the lower one 

 shorter, almost disappearing in more posterior segments). 



Notosetae long, delicate, flowing, curving inward over dorsum, 

 simple, tapering to capillary tips. Neurosetae of several kinds (see 

 pi. 7, fig. 5, in Verrill, 1881): LTpper few simple, bipinnate, with acute 



