ANNELIDA FROM BERMUDA. 32Sf 



Fam. THELETHUSID.E. 



AEENICOLA Lamarck. 

 Arenicola cristata Stimpson. 



Stimi'SOX. Proc. Boston Soc. Nat. His., vol. v, p. 114. 

 QUATKEFAGES. Hist. Nat. (les Aiiii., vol. ii, p. G73. 1865. 



The posterior (non-branchiated) segments of this species are set off 

 from each other by deep constrictions. 



On the first segment, back of the branchiae, the feet are represented 

 by two stout conical cirri on either side, distant from each other by 

 about the diameter of the base of each. 



On the remaining nine segments there is but a single cirrus on eacfi» 

 side, and these pass to the ventral surface, and stand close together. 



Fam. CIRRATULIDiE. 

 CIERATULUS Lamarck. 



CiRRATULUS TENUIS n. sp. 

 (Plate XI, Figs. 56, 57.) 



Head short, bluntly rounded in front; no eyes. First three segments 

 without setoe or cirri. Third segment a little longer than the fourth r, 

 as long as the first two together. 



Lateral branchiae begin on the fourth segment, and exist, on the an- 

 terior third of the body, on all segments ; not so numerous further back. 



Dorsal branchiae on the fifth, sixth, and seventh setigerous segments.. 

 two or three on each side of each segment; not forming a complete 

 transverse series, but leaving a naked median space. Branchial cirri 

 all long, not diifering from each other. 



The setic of the anterior segments are capillary in both rami, long, 

 delicate, 7-10 in each fascicle. 



At about the fifteenth setigerous segment the ventral setae begin to 

 be replaced by uncini, and after a few segments the capillary setae dis- 

 appear. There are at first three of the ventral uncini; then two ; while 

 on the posterior segments there is but one to each ramus. At about the 

 twentieth setigerous segment uncini appear in the dorsal rami ; both 

 kinds of setae remain to the end. 



The body is convex above, compressed, flattened below; segments' 

 very short but distinctly defined ; from the middle the diameter doorcases 

 slightly, backward. 



^STuraber of segments, 110. 



Length, aO'"'". 



Diameter, 2™°>. 



