ANNELIDA FROM BERMUDA. 309 



the middle line of the body ; passing- from this line ontward they become 

 somewhat narrower. 



Feet biramous; ventral ramus (Fi^r. 12) a little longer than the dor. 

 sal, curved upward, tapering slightly from base to apex, bluntly rounded 

 externally. It carries a finger-shaped cirrus which originates near the 

 base of the rannis. Dorsal ramus (Fig. 11) somewhat conical, truncated 

 externally, and bearing a short cirrus, which arises near the center of 

 the truncated surface. The two rami are very close to each other. 

 Setaj of the ventral ramus of two kinds, both compound; in the upper 

 I)art of the bundle from two to six, elongate (Fig. 13), delicate, with 

 long capillary appendix ; all the others much shorter (Fig. 14), stouter, 

 with short appendix. Seta3 of dorsal ramus (Fig. 15) from ten to fifteen 

 in number, all of one kind, thin, pointed, flattened, widest near the 

 center ; they arise from the ui)per side of the ramus. The anterior seg- 

 ments curve forwards, forming semicircles. All the segments are very 

 narrow. After the fifth segment the body has a uniform diameter to 

 the posterior third, after which it tapers uniformly to about one-half 

 the greatest width. The falling off in width is also rapid along the 

 first five segments. 



Color, in alcohol, pale light-yellow; ventral surface yellowish, or red- 

 disli-hrown. 



Body slightly convex above; flattened below. 



Length (largest specimen), 50'"™. 



Width, 3""". 



Specimen oidy 10""'" in length were also 3'""', or even 3.5'"™, in width. 



Fam. POLYNOID^. 



IIALOSYD]S^A Kinherg. 



Ofversigt Kon<i;l. Vetensk-Akad. Furliand., p. 364. 1855. 



Halosydna leucohyba {Schmarda). 



(Plate VII, Figs. lG-18. PI. VIII, Figs. 19,20.) 



Polyno'e Icurohyha Schmakda. Neue Wirbellose Thicro, vol. i, part ii, p. 153, figures 



iu text a, b, c, pi. xxxvi, lig. 308. 1861. 

 Pohjnoc lem-olnjha Quatuefages. Hist. Nat. des Ann., vol. 1, p. 251. 18G5. 

 f Antinoii leiicoliijba BauU). Liunean Society, Journal, vol. viii, p. 193. 



The width of the head, back of the bases of the antennae, exceeds the 

 length [Fig. 10). The head is slightly convex above, with a central de- 

 pression extending about one-half of the way back from the anterior 

 margin; sides strongly (convex; posterior margin straight; bases of the 

 lateral antenna) as long as the rest of the head. 



