98 CRUSTACEA MALACOSTRACA. III. 



Length of a specimen without niarsupium 2 mm. 



Male. Surface reticulate as in the female. Body scarcely three and a half times as long as 

 broad ; the difference in breadth between the anterior and the posterior segments (fig. 2 a) is smaller 

 than in the female, and fourth segment is not only narrower than the first, but even a little narrower 

 than the seventh. - - Head between six and a half and six times as broad as the distance between 

 the ends of the cephalic keels; the distal half of these keels is much more convex than in the female, 

 and the anterior margin of the front area is extremely concave (fig. 2 b). -- Antennulse and proximal 

 joint of antennae as in the female. 



The thoracic segments, excepting as to the breadth already mentioned, nearly as in the female; 

 even the ventral protuberances of the two posterior segments scarcely differ from those in the female, 

 but the protuberance on fifth segment (fig. 2 k) is distinctly lower. - Legs as in the female; no 

 natatory setae on the three posterior pairs. 



Abdomen (figs. 2 a and 2 1) distinctly broader than long and posteriorly scarcely produced. 

 Operculum a little longer than broad; the median lamella much broader before the middle than towards 

 the end, with the outer distal corner angular, and the terminal margin of each pleopod oblique. - 

 Uropods nearly as in the female. 



Length 1-8 mm. 



Remarks. ,V. reticulatus is instantly distinguished from all other species hitherto known by 

 the very conspicuous network on nearly the whole dorsal surface. The frontal emargination is un- 

 commonly deep, especially in the male. 



Occurrence. Taken by the "Ingolf" at a single station in the cold area. 



North of Iceland: Stat. 126: Lat. f>7i<)' N., Long. i532' W., 293 fath., temp, -r- 0-5; 6 spec. (3 d*, 3 .). 



60. Nannoniscus inermis n. sp. 

 (PL IX, figs. 4 a 4 f). 



Female. Body about three and one-third times as long again as broad. Second and third 

 thoracic segments nearly one-third as broad again as sixth or seventh segment, and the lateral margins 

 of fourth segment converge only moderately backwards. 



Head a little more than four and a half times as broad as the distance between the anterior 

 ends of the cephalic keels (fig. 4 a), and the anterior margin of the front area is slightly convex. - 

 Antennulse (fig. 4 b) very characteristic; first joint longer than broad; second joint a little longer than 

 the first, rather slender and slightly thicker towards the end, which has the angles, at most, feebly 

 protruding; third joint is unusually long and totally visible; fourth joint with the process somewhat 

 long, but reaching slightly beyond the middle of the vesicle, which is uncommonly narrow and long, 

 between two and a half and three times as long as broad. -- Antennae slightly more than half as 

 long as the body; fifth and sixth peduncular joints about equal in length, slender and somewhat 

 thickened at the end ; flagellum somewhat longer than sixth joint, with more than its proximal half 

 unjointed, while the distal part is divided into 8 joints; squama small, triangular, slightly longer than 

 broad, acute (fig. 4 b). 



Second thoracic segment with a rather slender spine on the antero-lateral angles, and a nearly 



