CIRRATULUS SININCOLENS. 377 



Locality. Off Peru: Sta. 4653 (lat. 5° 47' S., long. 81° 24' W.). Depth 

 536 fms. Bottom of dark brown volcanic mud. Bottom temp. 41.3° F. 

 12 November, 1904. Two specimens. 



This species is exceptional in its large size and in the considerable depth at 

 which it lives, the members of the genus being almost exclusively littoral. It 

 has resemblances to C. capensis Schmarda, but has the special branchiae on the 

 first instead of on the second somite, has the somites of a different proportion, 

 the ventral spines without the curvature characterizing those of that species, 

 etc. Cirratulus capensis is also a large species, the maximum length recorded 

 being 200 mm., with a maximum width of 9 nun., which is considerably smaller 

 than the type of the present species. 



Cirratulus sinincolens, sp. nov.^ 

 Plate 70, fig. 7-10. 



The general color of the types at present is grey, in parts of veiy slight 

 brownish tinge. 



The larger of the two type-specimens is incomplete caudally, sixty five 

 somites being present. Its total length is about 60 mm. and the maximum 

 width 11.5 nun. The smaller specimen is complete. It has a total length of 

 about 95 mm., a maximum width of 7.5 nun., and consists of 107 or 108 somites. 

 The general form of the body is essentially as usual in the genus, broadest and 

 highest in front of the middle, and tapering at both ends. The dorsal surface 

 strongly convex, the ventral flat. 



The prostomium is short and broad. In outline as seen from above with 

 the anterior margin semicircularly rounded, on the lateral portions more flat- 

 tened, and giving the appearance, roughly, of a trapezium or truncate triangle 

 with the sides toward the base flaring ectad. The prostomium is much highest 

 across the caudal end, being strongly transversely depressed in front and the 

 slope of the caudal portion very steep, not marked with any distinct longitudinal 

 furrow. On each side separated from proboscis by a deep, vertical sulcus which 

 extends from the border of the mouth toward the dorsum, upon which it does 

 not extend, setting off a caudal band. This band is essentially fused with the 

 peristomium above. The sulcus is weak in the smaller specimen. 



The peristomium is abruptly more slender than the succeeding portion of 



' sinus, gulf, incolere, to inhabit. 



