53 



2 short successive dentiform projections, antepenultimate joint about the length 

 of the last 2 joints combined; 3rd and 4th pairs, like the 2 preceding pairs, 

 with the basal joint unarmed. Uropoda with the raini subequal in length and 

 about half as long as the stem, inner ramus rather narrow, with the 1st joint 

 shorter than the other 2 combined, spinules of the inner edge about 12 in 

 number (7 on the 1st, 3 on the 2nd, and 2 on the last joint), apical spine rather 

 produced, mucronate. Telson scarcely reaching as far as the stem of the uro- 

 poda, proximal half thick, cylindrical, distal half gradually narrowed, and armed 

 on each side with about 9 spinules, apical spinules a little larger than the lateral. 

 Colour whitish, joints of the superior antennae and 1st pair of legs tinged at the 

 end with reddish brown. Length amounting to 9 mm. 



Adult male of the usual slender form. Carapace much shallower than 

 in the female and almost 3 times as long as the exposed part of the trunk, 

 exhibiting on each side a slight longitudinal keel, pseudorostral projection com- 

 paratively shorter than in female, ocular tubercle rather large and prominent. 

 Last pedigerous segment considerably produced at the lateral corners. Caudal 

 segments armed dorsally with scattered denticles. The several appendages trans- 

 formed in the usual manner. Length amounting to 10 mm. 



Remarks. This form was first described by Prof. Lilljeborg from Kulla- 

 berg in Skane as Cuma tumida, and was subsequently observed by Dr. Daniels- 

 sen on the west coast of Norway. At first I believed it to be the Alauna rostrata 

 of Goodsir, and that it was the same species as Diastylis Icevis of Norman ; but, 

 as stated above, this supposition has turned out to be wrong. It is unques- 

 tionably specifically different from that form, and easily distinguished both by its 

 more robust form of body, and by several structural details, mentioned in the 

 above diagnosis. 



Occurrence. I have found this form in several places on the Norwegian 

 coast, from the Christiania Fjord to the Lofoten Islands, though nowhere in any 

 considerable number. It is a true deep-water form, scarcely occurring in shal- 

 lower water than 30 fathoms, whereas it descends to depths of more than 300 

 fathoms. Only a few specimens of the adult male have come under my notice. 



Distribution. Kullaberg (Lilljeborg), Kattegat (Meinert). 



