CURIOUS EYES 269 



Soutliern Ocean, in 1,950 fathoms, at latitude 53° 55' south, 

 but afterwards it was taken at a depth of 1,11-0 fathoms, 

 north-west of Finmark, by the Norwegian North Atlantic 

 Expedition. This is one of the instances in which a species 

 has only been found far to the north and far to the south, 

 yet it seems hasty to infer that such species will not in 

 time be discovered in many intermediate localities. Boreo- 

 mysis scyiolioijs is gigantic for a Mysidan, attaining a length 

 of more than three inches. In this genus there are seven 

 pairs of marsupial plates, which are attached to the second 

 maxillipeds and the following limbs. Apparently all the 

 rest of the Mysidse are content with a much smaller num- 

 ber of incubatory lamella. Boreomysis is without the 

 abnormal characters of the male found in Petalojjhthahnns, 

 and it has the telson apically incised. 



Amblyojjsis was altered into Amhlyops by Sars in 1872. 

 The name has reference to the character of the eyes, which 

 are 'imperfectly developed, transformed into two immobile 

 plates, extending horizontally in front of the carapace and 

 contiguous in the middle.' There are only two species, 

 the Norwegian AmhJyojms abbreviata, and from the 

 Southern Ocean Amblyo]jsis crozetii. In this genus the 

 legs are tolerably strong, having the sixth joint subdivided 

 into three articulations, and the terminal joint unguiform ; 

 the telson is not incised at the apex. 



Paeudomma has the ' eyes quite rudimentary, forming 

 merely broad petal oid expansions of the ocular segment, 

 partly connate in the middle, and not exhibiting the slightest 

 trace of pigment or visual elements.' Here the legs are 

 exceedingly slender, the sixth joint subdivided as in the 

 preceding genus, but the terminal joint obtuse, not ungui- 

 form. The telson is not incised. Three northern and two 

 southern species have been described, Pseudomma trunca- 

 fiim, S. I. Smith, being arctic, and Pseudomma Sarsii, v. 

 Willemoes Suhm, antarctic. 



Mysis, as understood prior to the recent restriction of 

 the genus, has the sixth joint of the trunk-legs subdivided, 

 and the fourth pair of pleopods in the male developed into 

 long backward-directed stilets, the third pair being also 



