70 AXEL OHLIN, ARCTIC CRUSTACEA. 



known frora a single specimen from Greenland, Låter on, in 

 his clasj^ical vMoiiographi över de ved Norges Kyster fore- 

 komniende Mysider», III. 1879, the same author gave a full 

 diagnosis of the genus. He considers the structure of the mar- 

 supium in the female as its most distinctive feature, this being 

 here composed of seven pairs of lamella?, whilst, in all other 

 Mysideans, it is formed by three pairs at the utmost. 



Petalophthalmns Willemoes-Suhm is the only one that 

 shares that characteristic with Boreomysis. Besides that, the 

 structure of thep leopods in the male being all natatory, with 

 very elongate branches, and the rudiraentary auditory appar- 

 atus make the genus very distinct. In the same genus he 

 included two other species also occurring in the deepest 

 parts 100 — 400 fathoms of the Norwegiau Fiords, viz., Bo- 

 reomysis tridens G. O. Särs, and Boreomysis megalops G. O. 

 Särs. On the Norwegian North Atlantic Expedition were ob- 

 tained the two species to be mentioned below; and, in his re- 

 port on the Challenger Schizopoda, Särs added two more 

 species to the genus, viz. Boreomysis ohtusata and Boreomysis 

 microps from the North Pacific and North Atlantic resp., 

 both from considerable depths. Thus the genus comprises, 

 at present, seven species, all of which are probably bathy- 

 pelagic forms. 



'id'. Boreomysis nobilis G. O. Sars. 

 Fig. 3. 



187ii. liorcoiuysis uobilis G. O. Sars, Criist. et Pycuogou. uova etc, 



1. c. p. 428. 

 1885. >; ■» G. O. Sars, Norweg. North Atl. Exp. I, 



p. 54, pl. 5, fig. 22—28. 

 1887. » » Hansen, Ofv. vestl. Gröulauds Fauua etc, 



1. c. p. 214. 



Localities: 

 iu 1900: 



stat. 21. East Greenland, off Kaiser Franz Joseph Fiord betwecn 

 Bontekoe Island and Mackenzie Bay, deptb 250 iii., luud, 

 8/VIII, several spec. 

 » 25. East Greenland, entrauce of Kaiser Frauz Joseph Fiord, 

 depth 200 — 300 ra., mud, 14 /VIII, three spec. 



