456 G. 0. SARS, 



part, with tlie lateral lobes obtusely pointed, aud each having 3 apical and 

 2 lateral spiuules. Length of adult female 6 mm. 



Remarks. — This new species is easily distiugnishable by its slender 

 and compressed body, the conspicuously spinulose urosome, the uniform 

 shai)e of the basal Joint of the 3 posterior pairs of pereiopoda, and finally, 

 by the great development of the last pair of uropoda. 



Bescription. — Fully adult female specimens do not exceed in length 

 G mm., male specimens are, as usual, a little larger. 



Tlie body (see fig. 12) is exceedingly slender and mnch compressed, 

 with the mesosome and metasome quite smooth. "~ 



The urosome, however, exhibits dorsally a very conspicuous spinulose 

 armature, each segment having 3 fascicles of slender, very much upturned 

 spinules, one median and 2 lateral. Each fascicle contains, as a rule. 2 

 juxtaposed spinules, sometimes accompanied by a small hair. 



The cephalon does not attain the length of the first 2 segments of the 

 mesosome combined, and has the lateral lobes very obliquely truncated, so 

 as to form anteriorly a projecting acute angle. 



The anterior pairs of coxal plates are not very large, though a little 

 deeper tlian the corresponding segments, and they are quite smooth. The 

 1st pail' are scarcely expanded distally, and are obtusely rounded at the tip. 

 The 4th pair (see fig. 16) are not particularly broad, and they have the 

 posterior expansion obtusely truncated. 



The epimeral plates of the metasome are well developed, the 1st pair 

 being, as usual, rounded, whereas the 2 other pairs, and especially the last, 

 are acutely produced at the lateral coi-ners. 



The eyes are of moderate size, aud oblong oval in form, being placed 

 close to the anterior edges of the head. 



The superior antennae are very slender, exceeding half the length of 

 the body, and have the peduncle, and partly also the flagellum, clothed 

 posteriorly with slender delicate setae. The 1st joint of the peduncle is, as 

 usual, the largest, though not much longer than the 2nd, whereas the 3rd 

 is veiy much smaller. The flagellum is fully twice as long as the peduncle, 

 and composed of about 20 articulations. The accessory appendage (see fig. 13) 

 is rather slender, aud 4-articulate. 



The inferior antennae are considerably shorter than the superior, and, 

 especially in the male, very densely clothed posteriorly with rather long 

 sette. The flagellum is about the length of the peduncle. 



The gnathopoda, unlike what is the case in the 3 preceding species, are 

 in both sexes nearly equal-sized. In the female (figs. 14, 15) they are rather 

 feeble in structure, and differ somewhat in the shape of the propodos, which 



■tira.-MuT. CTp. 2S6. 36 



