254 U.S. NATIONAL MUSEUM BULLETIN 227 



specimen of the host, ranging in size from a few (7) to numerous 

 (about 110) segments. The parasites are considered to be possibly 

 the young of Notocirrus spiniferus (Pettibone, 1957b; see also p. 275). 



Material examined. — Numerous specimens from Massachusetts 

 (Duxbury, Woods Hole region, Nantucket Sound, Vineyard Sound, 

 Buzzards Bay; Cape Cod, Provincetown, Wellfleet, Barnstable), 

 Rhode Island (Potters Pond, Plum Beach), Virginia (Chincoteague 

 Bay area, Chesapeake Bay), North Carolina (Beaufort), South 

 Carolina (Skull Creek, Parris Island), Mississippi (Biloxi), Louisiana 

 (Sabine Lake) . 



Distribution. — Massachusetts (Duxbury) to Florida, West Indies, 

 Gulf of Mexico, Panama, south to Brazil. In low water to 45 fathoms. 



Genus Hyalinoecia Malmgreii, 1867 



Type (monotypy): Hyalinoecia tubicola (O. F. Miiller, 1776). 

 Contains only one New England species. 



Hyalinoecia tubicola (O. F. Miiller, 1776) 



Figure 65d 



Hyalinoecia artifex Verrill, 1880, p. 357; 1885a, p. 524, pi. 41, figs. 178-179; 

 1885b, p. 429.— Procter, 1933, p. 139. 



Hyalinoecia tubicola siricta Moore, 1911, p. 280, pi. 18, figs. 96-97. 



Hyalinoecia tubicola Augener, 1906, p. 135. — Fauvel, 1923, p. 421, figs. 166,i~q; 

 1953, p. 261; 1957b, p. 214.— Chamberlin, 1919, p. 315.— Monro, 1936, p. 

 152.— Berkeley and Berkeley, 1941, p. 37. — Hartman, 1944a, p. 340, pi. 14, 

 fig. 6, pi. 17, figs. 14-15; 1944d, p. 46; 1951, p. 52.— St0p-Bowitz, 1948a, p. 

 65.— Wesenberg-Lund, 1950a, p. 27; 1950b, p. 69.— Fauvel and Rullier, 1959, 

 p. 939.— Knox, 1960a, p. 126.— Clark, 1960, p. 23.— Day, 1960, p. 356. 



Description. — Length up to 215 mm., width up to 8 mm., segments 

 up to 180. Body nearly linear, depressed dorsoventrally except on 

 anterior end. Prostomium short, subconical, with 2 ovoid frontal 

 antennae, 5 occipital antennae with short, faintly ringed bases or 

 ceratophores, the 3 dorsal occipital antennae longer than the ven- 

 trolateral ones, the median one the longest. Usually without eyes 

 (may be present, especially in young). A pair of large globular 

 ventral palps present. First or tentacular segment a short apodous 

 ring without tentacular cirri. First setigerous segment about twice as 

 long as the tentacular segment, with parapodia enlarged, turned 

 forward and downward, clawlike. Second setigerous segment slightly 

 longer than the following. Parapodia of second and third setigers 

 somewhat enlarged and turned downward and slightly forward. 

 From the fourth setiger on, parapodia directed laterally. Dorsal 

 cirri short, subulate, nearly as long as the parapodial lobes, becoming 

 more cirriform toward setiger 30. 



