CRUSTACEA MALACOSTRACA III 



J 43 



The front area between the basal joints of the antennnlse is rather narrow, longitudinally eon- 

 cave with the lateral margins raised (fig. 2 b) and it tapers strongly forwards, but instead of being 

 horizontal as in £. cornuta or E. Hanseni its anterior part, seen somewhat from the side, slopes down- 

 wards and terminates below without being well marked off from the front just above the vaulted 

 clypeus. - - First joint of the antennulse (fig. 2 e) shaped as in E. cornuta, especially as the autero-interior 

 lobe is somewhat short, considerably broader than long; second joint inserted and shaped as in E. cor- 

 nuta, considerably thicker in the male than in the female, a little or somewhat shorter than the more 

 slender third joint. — Antennal squama (fig. 2 d) oblong-triangular, terminating in a spine, and slightly 

 more than half as long as the breadth of third joint. — Maxillipeds (fig. 2 e) have the second joint, 

 counted to the articulation of third joint, half as long again as broad (in this respect it agrees with 

 E. cornuta, as Sars has figured the second joint too short); the distal terminal corner of the epipod 

 more rounded than in E. cornuta. 



Thoracic segments (fig. 2 a) nearly as in E. cornuta; the epimera a little more produced than 

 in that species. 



The female abdominal operculum very different from that in /:. cornuta. Seen from below (fig. 

 2 k) it is broadest much before the middle, and then the most lateral part at each side constitutes a 

 rounded rather short lobe directed outwards; the great portion of the operculum behind these lobes 

 is triangular with each lateral margin a little sinuate and the end narrowly rounded; the surface has 

 a high keel from somewhat from the base to near the posterior end. Seen from the side (fig. 2 i) the 

 operculum is highly vaulted; its lower margin is bent, forming an angle of about ioo°, which is placed so 

 far backwards as the insertions of the uropods; the lower margin in front of that angle is long and 

 straight, and behind the angle it is somewhat short and almost vertical on the lower surface of the 

 abdomen. — The male abdominal operculum also differs much from that in E. cornuta. Its median 

 lamella (fig. 2 f) is narrower, about three times as long as broad and more constricted near the middle; 

 tlie terminal part of each pleopod forms a lobe (fig. 2 g), which is conspicuously longer than broad, 

 with setae along its somewhat convex outer margin and the rather narrowly rounded end; at the 

 outer base of the lobe the pleopod is suddenly a little broader, so that a small and low, rectangular 

 and protruding part is observed. Each lateral plate (fig. 2 h) has a kind of low but very broad, rounded 

 lobe on the basal part at the outer margin, and this lobe has some marginal hairs; the distal half of 

 the outer margin is considerably concave, and the terminal part of the plate is produced into a lobe 

 as long as broad, with both margins concave and the end narrow with a few setse; the copulatory 

 organ has its second joint rather short, only a little more than half as long as the plate, and the part 

 containing vesicle and duct is only somewhat longer than the part from base to vesicle; the distal part of 

 the inner margin, which runs across the coupling hook, is more concave than in E. cornuta. — Uropods 

 (fig. 2 1) with the peduncle thick, the eudopod considerably longer and much thicker than the endopod. 



Length of large males from the cold area 9—9*3 mm., of females 9—11-5 mm., but the two 

 largest females, both from the "Ingolf" Stat. 103, have no marsupium and are ir2 and 115 mm. long. 

 The length of adult specimens from the warm area 5-5 to 7 mm. 



Remarks. E. inermis is abundantly distinguished from E. cornuta by having the anterior 

 part of the front area curved downwards and without any freely protruding end, by the unequal length 



