46 Gr. O. Sars. 



marked, ante-anal denticles about 20 pairs, terminal claws 

 slender, each with 2 distant secondary denticles. Length of 

 adult female 0,74 mm. 



Remarks. — This form looks very like the well-known 

 European species, C. macrurus, Müll., but is at once distin- 

 guished by the total abscence of the denticles found at the 

 infero-posteal corners of the shell in that, as also in the 

 other known species of the genus. 



Description of the female. 



The body, as in the other species, is highly compressed, 

 and provided with a distinct crest, extending aloug the 

 dorsal face of both the shell and the head. Seen laterally 

 (fig. 9), the shell exhibits an oblong form, being broadest in 

 front, and narrowed towards the posterior extremity, which 

 appears obtusely rounded, without any angle below, and 

 with the upper corner almost obsolete. The dorsal margin 

 forms a rather even curve until the tip of the rostrum, 

 whereas the ventral one appears somewhat flexuous, 

 being rather protuberant in front, and assuming behind a 

 more straight course. The head is rather large and some- 

 what procumbent, terminating in a blunt, cleflexed rostrum. 

 The fornical edge is but very slightly curved, and joins the 

 shell on each side at a very acute angle. 



The surface of the shell is sculptured with well-marked 

 longitudinal striæ, about 18 on each side, and exhibits 

 besides, in the most anterior part of the valves, a number 

 of closely set, curved transverse lines. The iuferior edges 

 of the valves are fringed with delicate bristles, which suc- 

 cessively diminish in length behind, and disappear altogether 

 at some distance from the posterior extremity. Not even 

 the slightest trace of any denticles is found behind the 



