597 



Ixcnmrkf. — The pi'esent species is nearly allied to P. faJcattis, but 

 easily distinguisliable by its very inferior size, and more particularly by 

 the structure of the posterior gnathopoda in the two sexes. As above stated, 

 the detail-figures given by Boeck in his great work, and assigned to P. falcatus, 

 ai'e more pi'operly referable to tlie present species. 



Occurrence. — I have met with this form in several places, both on 

 the south and west coasts of Norway', as also in the Trondhjemsfjord, and 

 northwards along the Nordland coast up to Hammerfest. It is generally found 

 clinging to Hydroidse growing in depths varj'iiig from 20 to 100 fathoms, 

 and is never met with in company with P. fnlcafiis:, whicli is a more pro- 

 nounced littoral form. 



Distrihiilion. — British Isles (Robertson), coast of France (Chevreux). 



10 Podocerus odontonyx, G. 0. Sars, n. sp. 



(PI. 213, fig. 2). 



Very like the preceding species both as to size and general appear- 

 ance. Lateral lobes of cephalon rather broad, and slightly emarginated at 

 the tip. Eyes comparatively large, rounded, with brownish pigment. An- 

 tennae almost exactly as in P. pusiUus. Anterior gnathopoda likewise very 

 similar. Posterior gnathopoda in male, however, rather diiferently shaped, 

 with the propodos oblong oval in form, and sending off from about the middle 

 of the lower edge, a comparatively small, anteriorly-pointing, thumb-like 

 pi'ocess, obliquely truncated at the tip, and defined from tiie anterior triangular 

 lappet by a deep angular incision ; dactvlus exceedingly strong and curved, 

 with its posterior edge projecting in the middle as a triangularly-pointed, 

 dentiform projection. Pereiopoda, uropoda and telson nearly as in the pre- 

 ceding species. Body variegated with partly confluent patches of a dark 

 brown colour. Length of adult male 5 mm. 



Remarks. — Tlie validity of this species may perhaps be questioned, 

 since, both in size and in most of the anatomical details, it agrees verj^ closely 

 with P. pusiUns. The structure of the posterior gnathopoda in the male is, 

 however, so remarkably diiferent both in the shape of the propodos and 

 especially in the very conspicuoiis dentiform projection of the dactylus, that 

 I have felt justified in separating it as a distinct species. The ]\ Herdmani 

 of Walker would seem to be very nearly allied to the present form, and may 

 indeed turn out to be the same species. 



T9 — Crustacea. 



