92 CRUSTACEA MALACOSTRACA. III. 



The thorax, as already mentioned, differs somewhat from that of the female in outline, as first 

 and second segments are only slightly broader than the sixth segment; the antero-lateral angles of 

 first segment with spines, of second and third segments with setae as in the female; the rounded ven- 

 tral posterior protuberance (fig. 3 i) as in the other sex. First pair of legs (fig. 3 g) nearly as in the 

 female; seventh pair (fig. 3 h) differs from those in the female in having the most distal spine on fifth 

 joint short, while a long, stiff seta has replaced the long spine in the female ; furthermore the three 

 posterior pairs have some long setae on a part of the upper margin of fifth joint, and many extremely 

 long setae on the upper margin of sixth joint. 



Abdomen (figs. 3 a and 3 i) differs in outline conspicuously from that in the female, as the 

 lateral margins are scarcely or slightly convex, converge to a point somewhat beyond the insertions 

 of the uropods, and then each margin bends abruptly much more inwards, thus constituting half of 

 the posterior margin and being slightly concave; the end of abdomen is angular, but not acute. - 

 Operculum slightly longer than broad; the median lamella is widened near the end, and each outer 

 angle produced into a very conspicuous, slender process directed somewhat backwards and much out- 

 wards; consequently the posterior margin of each pleopod is convex. Uropods about as in 

 the female. 



Length 1-9 mm. 



Remarks. As shown in the key (p. 89) N. simplex is easily separated from the other forms 

 of this section, and in reality from most of the other species of the genus seen by me, in having well 

 developed spines on the lateral angles of first segment, and only stiff setae on the angles of second 

 and third segments. In general appearance it is nearly similar to N. oblongus G. O. S., but the outline 

 of the male abdomen is different, and the postero-lateral processes of the median opercular lamella 

 afford a good character. 



In the marsupium of a female (from Stat. 90) a species of Spharonella with ovisacs (family 

 Choniostomatidae) was found. 



Occurrence. Taken by the "Ingolf" at two stations in the warm area. 



West of Iceland: Stat 90: Lat 64^' N., Long. 29o6' W., 568 fath., temp. 4-4; 2 spec. (?). 



South-West of Iceland: Stat 78: Lat. 6o37' N., Long. 2752' W., 799 fath., temp. 4-5; 10 spec. 

 (6?, 4c ?). 



55. Nannoniscus oblongus G. O. Sars. 

 (PI. VIII, figs. 4 a 4 f). 



1870. Nannoniscus oblongus G. O. Sars, Forh. Vid. Selsk. Christiania for 1869, p. 164. 

 ! 1897. G. O. Sars, Account, II, p. 119; PI. 50. (partim; the animal described and 



figured as the male is the female of N. crassipes n. sp.). 



Female. Body from somewhat less to somewhat more than three times as long as broad, 

 with second and third segments only one-fifth or one-sixth as broad again as the sixth segment, 

 while the margins of fourth segment converge only moderately backwards. 



Head from six to eight, frequently about seven, times as broad as the distance between the 



