CRt STACKA MAI.ACOSTRACA. 111. 



.tl of Jan Mayen: Stat 116: Lat. TO O O$' N, Long. 8a6' W., 371 fath., temp. 4- oV, i spec. (poor). 

 Besides, it has been taken by the Ilnd Atndrup Kxped. at East Greenland in Forsblad Fjord, 

 Lat ja'i/' N., 9040 fatlu, i fine spec 



57. Nannoniscus analis n. sp. 

 (PL VIII, figs. 6a-6k; PL IX, figs, i a-i b). 



Female. Body (fig. 6 a) from three to nearly three and a half times as long as broad, with 

 second and third thoracic segments considerably broader than, viz. even a little more than one-third 

 as broad again as, the two posterior segments, while the lateral margins of fourth segment converge 

 only moderately backwards, and the fifth segment is conspicuously broader than the sixth. 



Head (fig. 6 a) four times, or a little more than four times, as broad as the distance between the 

 .interior ends of the cephalic keels, and the anterior margin between these keels is feebly concave. - 

 Antennulx (fig. 6c) nearly as in N. obhngus. -- Antenna- nearly half as long as the body; flagellmn 

 inure than half as long again as fifth or sixth peduncular joint, 13-jointed, with first joint about as 

 long as the three following joints; squama marked off, conical and considerably shorter than the 

 diameter of third joint 



Second thoracic segment with a distinct, or even somewhat long, spine on the antero-lateral 

 angles, while the angles of first and third segments have no spines, but frequently a short, fine seta. 

 The median ventral part of seventh segment raised as a high protuberance (figs. 6 i and 6k) lying 

 close to the front margin of the abdominal operculum, and anteriorly stretching forward on the post- 

 erior part of sixth segment, which, besides, has a tubercle of its own. Legs somewhat similar to 

 those in JV. simplex^ but the accessory claw is more or less feeble on all pairs; the first pair (as in the 

 male, fig. 6 e) are distinctly thicker than the second or third pair (fig. 6 f), with two small spines on 

 the lower margin of fifth joint, while fifth joint of third pair has five spines; the three posterior pairs 

 (fig. i b) with still fewer spines than in A', simplfx and no natatory seta. 



Abdomen (figs. 6 a and 6i) almost as long as broad, with the outline very characteristic, as the 

 lateral margins outside the base of the uropods are conspicuously concave with an angular bend, 

 because they turn somewhat suddenly inwards and then nearly abruptly backwards, as the median 

 posterior part of abdomen is produced almost as a lobe rather broadly rounded at the end. -- Oper- 

 culum (figs. 6 i and 6k) slightly longer than broad, posteriorly rounded; its proximal median part is 

 highly raised and produced into a long, strong, acute process directed backwards and considerably 

 downwards. Uropods (fig. 6 i) with the peduncle short, the endopod somewhat slender and not quite 

 twice as long as the very slender exopod. 



Length of large specimens 27 nun. 



Male. Body not quite three and a half times as long as broad; the anterior third of the 

 thorax only a little broader than the two posterior segments. - - Head (fig. 6 b) between five and four 

 and a half times as broad as the distance between the ends of the cephalic keels, and the anterior 

 margin of the front area is a little concave. Antennulae as in the female. Antennae (fig. 6 d) nearly 

 as in the female excepting the flagellum, which is extremely different; the flagellum has its proximal 



