PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 173 



Buccal segment large, somewbat swollen. Jaws small, light brown, 

 strongly curved, with slender, sharp tips, the edge moderately serrulate. 

 Denticles (or paragnaths) not observed, the proboscis being retracted. 

 Parapodia of anterior segments small, the two rami of nearly equal 

 length, and with similar fascicles of setai, the lower ones most numerous, 

 the upper hngula small, subtriangular, terminated by the slender, taper- 

 ing, dorsal cirrus, which, at about the fifth segment, is more than twice 

 as long as the lingula and reaches about to the end of the setse. Ventral 

 cirrus short, tapering. Farther back, at the eleventh segment and beyond, 

 the rami become more unequal, the ui)per lingula develops into a long, 

 flat, narrow, tapering branchia, bearing the filiform dorsal cii*rus at its tip. 

 At the fifteenth segment and beyond the branchia is decidedly longer 

 than the parapodia, curved directly upward, and about eight times as 

 long as its width in the middle, and more than half the diameter of the 

 body, rather abuptly narrowed at tne tip, and terminated by the long, 

 slender cirrus, which equals or exceeds the branchia. In the enlarged 

 base of the branchice there is a circular, thickened, white, round spot, 

 due to an internal organ. On the setigerous lobe of the upper ramus 

 is a narrow-lanceolate, lingula-like process, extending from the setiger- 

 ous lobe as far as the tips of the setae. On the lower ramus there are two 

 similar lin guise, one of which is terminal, and the other is situated at 

 about the distal third, on the lower side. Ventral cirrus small, slender, 

 tapered, single on the first sixteen segments ; on the seventeenth and 

 subsequent segments there are two equal ventral cirri, arising close to- 

 gether. Setse in this region form a large fascicle in each ramus, with a single 

 aciculum dividing each fascicle into two groups. The setie in the upper 

 ramus have a very long, slender, smooth, nearly straight, terminal joint, 

 flexible at tip, and not distinctly flattened, even toward the base. In 

 the lower ramus, the terminal joint is not quite so long, slender, and nar- 

 row, but distinctly flattened, and with the edge very finely serrulate ; 

 these are very slightly curved, but not abruptly bent, near the base. 

 Diameter of the anterior part of the body, G™'" to 7""". Color of body pale 

 brownish or pinkish; branchia and bases of parapodia bright red; seti- 

 gerous lobes greenish, the setae dark at base. Described from life. 

 Dedicated to Professor H. E. Webster, who has largely contributed to 

 the knowledge of American Annelids. 



Twenty-four miles east of Cape Cod, 122 fathoms, soft mud (U. S. 

 Fish Commission). Only one specimen, which lacks the posterior por- 

 tion of the body. Closely related to C. Loveni Malmgren, but the 

 latter has the branchial organs cirriform and slender, and the double 

 ventral cirri are figured upon the tenth segment; the setae of the 

 lower ramus are also represented with the terminal joint abruptly bent 

 at base, wider, and much more strongly serrulate than in our specimen. 

 It is possible, however, that the two may be only sexual forms of one 

 species. 



