177 



somewhat emarginated, and l)earing a single apical spinule. Body whitish. 

 pellucid, without any distinct pigmentation. Length of adult female 18 mm. 



Remarks. From all the species previously described, this form is 

 easily distinguished by the absolute want of eyes, moreover by the dorsal! v 

 carinated cephalon, and the distinct dentiform projection of the anterior pairs 

 of coxal plates. It is, next A. Escliriclitii, the largest of the indigenous 

 Ampeliscse. 



Occurrence. Of this form, 2 specimens were collected during tin- 

 Norwegian North Atlantic Expedition, outside the coast of Helgoland (Stat. 

 147), in a depth of 142 fathoms. A few much smaller specimens I found 

 subsequently at Hasvig, west coast of Finmark, in about the same depth, 

 and another specimen was collected by the author, some years ago, in the 

 outer part of the Trondhjemsfjord, at Bejan. It thus appears to be a true 

 Norwegian species. Out of Norway, it lias not yet been recorded. 



10. Ampelisca aeqvicornis, Bmzelius. 



(PI. 62, fig. 1). 

 Ampelisca ceqvicornis, Bruzelius, Kgl. Vet. Akad. Handl. Ill, p. 82, PL 4, tig. 16. 



Body rather stout, with the back rounded, not carinated. Cephalon 

 shorter than the 3 anterior segments of mesosome combined, and but slightly 

 tapering distally, front nearly transversely truncated, though the superior 

 corner is somewhat more projecting than the inferior. Anterior pairs of coxal 

 plates without any dentiform projection; 1st pair gradually widening below. 

 and considerably broader than the 2 succeeding pairs; 4th pair somewlial 

 deeper than it is broad, inferior edge about the length of the hind margin, 

 both defined from each other by an obtuse angle. Last pair of epimeral 

 plates of metasome rectangular. First segment of urosome with a very slight 

 dorsal carina, terminating with a somewhat projecting corner. Corneal lenses 

 distinct, though rather small, the lower pair placed at some distance from 

 the inferior corners of the front, close to the lower edge ; underlying pigment 

 well-defined, reddish. Antennae in female nearly equal in length, or the in- 

 ferior very little longer, about equalling half the length of the body, 2nd 

 peduncular joint of the superior ones rather elongated, last peduncular joint 

 of the inferior ones a little longer than the penultimate one, nagellum in 

 both pairs composed of about 24 joints provided posteriorly with fascicles of 

 slender setse. Gnathopoda of the usual structure, the anterior ones somewhat 

 stronger than the posterior. Dactylus of the anterior pairs of pereiopoda 

 scarcely attaining the length of the 2 preceding joints combined. The : 

 succeeding pairs unusually short, with the basal joint greatly expanded, lliat 



23 Crustacea. 



