04 



21. Orchomene pectinatus, G-. 0. Sars. 



(PL 23, fig. 3). 

 Orchomene pectinatus, G. 0. Sars, Oversigt af Norges Crustaceer, I, p. 80, PL 3, fig. 5. 



Form of body about as in 0. serratus, though perhaps a little more 

 robust. Lateral corners of cephalon acute, less projecting than in 0. crispatiis. 

 Coxal plates rather large, the 4 anterior pairs about twice as deep as the 

 body; 1st pair considerably dilated below, without however completely 

 concealing the buccal mass laterally, 5th pair somewhat narrower than in 0. 

 serratus. Last pair of epiineral plates of metasome rounded at the infero- 

 lateral corners, posterior edge slightly arched and divided into very coarse 

 and sharp somewhat upturned serrations, 12 10 in number. First segment 

 of urosome produced dorsally to a high compressed projection, sharply angulated 

 at the tip. Eyes narrow, slightly sigmoid in form, with imperfectly developed 

 visual elements ; pigment very pale, almost cream-coloured. Superior antennae 

 with the 1st joint of the peduncle very large and tumid; flagellum slender, 

 12 13-articulate ; accessory appendage about half its length and 7-articulate. 

 Epistomal plate of very considerable size and greatly projecting, evenly 

 rounded in front. Anterior gnathopoda rather slender, propodos only little 

 longer than the carpus and very slightly tapering distally. Last pair of 

 uropoda with the inner ramus fully as long as the basal joint of the outer, 

 and provided at the inner edge with 4 denticles. Telson very small, with 2 

 pairs of minute dorsal denticles, cleft extending about to the middle and 

 gradually widening posteriorly. Colour pale greyish white. Length of adult 

 female reaching 12 mm. 



Remarks. - Though very nearly related to the two preceding species, 

 this form may at once be 'distinguished by the imperfectly developed and 

 pale coloured eyes, the large and projecting epistomal plate, the very coarse 

 serrations of the last pair of epimeral plates of the metasome, and lastly 

 by the high compressed dorsal projection of the 1st segment of the urosome. 



Occurrence. - I first detected this form in the Varangerfjord at Bugo, 

 where a few specimens were collected at a depth of about 120 fathoms. In 

 no other parts of the Norwegian coast have I yet met with it, 



Distribution. North Atlantic: outside the great fishing banks off 

 the N.-West coast of Norway (Stat. 124, 192, 251 of the Norwegian North 

 Atlantic Expedition); Arctic Ocean W of Beeren Eiland (Stat, 312 of same 

 Expedition). 



