95 



well defined, rounded in form and carrying 4 slender marginal spines; inner 

 expansion of proximal joint comparatively small, scarcely extending beyond 

 the middle of the distal joint, and only provided with 2 spines of somewhat 

 unequal length. 



Length of the specimen examined 0.72 mm. 



Remarks. The identification of the above-described form as the male 

 of P. longisetosa cannot be contested, though some of the characters, especi- 

 ally the structure of the last pair of legs, are not in accordance with the 

 diagnosis previously given of the genus. 



Occurrence. The above-described male specimen was, like the female, 

 found at Farsund. I have not met with this form in any other locality on 

 the Norwegian coast. 



Gen. Argestes, G. O. Sars. 



Remarks. This is another genus originally founded only on a single 

 species, A. mollis G. O. Sars, found at Bukken, south west coast of Norway. 

 A slender Copepod recently found off the southern coast seems, according to 

 the structural details, to be referable to the same genus, though in its outward 

 appearance it looks rather different from the type species. A description of 

 this form is given below. 



77. Argestes tenuis, G. O. Sars, n. sp. 



(PI. LXVII). 



Specific Characters. Female. Body slender and narrow, with the 

 anterior division only slightly dilated, and the integuments very thin and 

 pellucid. Cephalic segment somewhat exceeding in length the 2 succeeding 

 segments combined, and without any distinctly defined rostral projection. Lateral 

 parts of the 3 succeeding segments rounded off; last trunkal segment smaller 

 than the preceding one. Urosome narrow cylindrical in form, and nearly 

 attaining the length of the anterior division, its segments very finely den- 

 ticulate at the hind edges, and clothed laterally with delicate adpressed spikes; 

 genital segment comparatively large and conspicuously protuberant below in 

 its anterior part; last segment somewhat larger than the preceding segment 

 and quadrangular in outline, anal opercle very broad and perfectly smooth 

 at the edge. Caudal rami about the length of the anal segment and narrow 

 linear in form, with all the setae issuing from the slightly thickened extremity, 

 the 2' middle apical setae very slender. Anterior antennae nearly as long as 



