27 



in the middle, more obtuse anteriorly and posteriorly and not depressed in the middle, so that 

 the upper border appears straight in a lateral view. The lateral carinae are straight, parallel 

 with the middorsal crest; they are rounded, but, properly speaking, must be regarded as the 

 lateral borders of the longitudinal grooves that exist on each side of the median carina, because 

 they are not defined by any groove or depression on the outer side. 



Like in Lept. gracilis Stimps. and in the form from Bass Strait, described in the Report 

 on the Challenger Macrura under the name of Lept. robusta, the outer orbital angle terminates 

 in a small acute spine, that is directed forward and the lower margin of vvhich makes a right 

 amde with the anterior border of the carapace; this spine is in the male a little larger than 

 in the female. Anterior margin of carapace setiferous, antero-inferior angle obtuse. 



In its general form the abdomen resembles that of Lept. robusta Stimps. The 5 th somite 

 (Fig. Sa) has the same shape, slightly compressed, the upper margin is blunt, but not carinate, 

 its posterior extremity unarmed. The pleura of the 4 th and 5 th somite of the male carry a small 

 obtuse tooth at the anterior end of their lower margin, but the posterior extremity is obtuse; 

 in Lept. robusta, however, the antero-inferior angle of the pleura of these somites is rounded, 

 without any tracé of a tooth, while the postero-inferior angle of the pleura of the 5 th somite is 

 acute, dentiform. In the female specimens, however, this small tooth on the lower margin of 

 the 4 th and 5 lh pleura does not occur. Sixth somite as long as 5 th and twice as long as wide 

 in a lateral view, posterior and postero-lateral margin like in Lept. robusta Stimps. ; the posterior 

 margin on each side with a small spine, foliowed laterally by the postero-lateral angle, which 

 is separated by a semicircular emargination from the subacute posterior extremity of the lower 

 margin. The transverse tubercle at the base of the upper surface is little prominent. While one 

 observes in Lept. robusta Stimps., near the posterior border of the lower surface of this somite, 

 on each side but a small tooth, L^ept. pugnax is armed, on the lower surface, on each side 

 with a long, slightly curved, acuminate spine; this spine, that measures about 

 one-fourth of the length of this somite, is implanted close to the lateral margin at the 

 posterior third and reaches almost as far backward as the posterior extremity of that margin. 



The telson, 2,1 mm. long in the ova-bearing female, just one and a half as long as the 

 6 th somite, shows the same shape and measurements as that of Lept. robusta Stimps., but the 

 upper surface is only armed with 2 pairs of spines. The spines of the basal pair are 0,25 mm. 

 long and 0,16 mm. distant from one another, i.e. one-fourth the width of the telson, while they 

 are implanted at the anterior ninth ; the posterior pair occur just behind the middle, close to 

 the lateral margins, and these spines are 0,17 mm. long. The armature of the tip with 5 pairs 

 of spines is exactly the same as in Lept. robusta Stimps. and here also the margins of these 

 spines are fringed with small denticles, except the outer margin of the spines of the 2 nd and 

 3 rd pair; the median spines, i. e. those of the i st pair, are 0,32 mm. long, those of the 2 ncl pair 

 0,66 mm., those of the 3 ld pair 0,58 mm. and hardly reaching beyond the median spines; the 

 spines of the 4 th pair are 0,33 mm. long and reach just beyond the extremity of the telson, 

 the spines of the 5 th pair, hnally, implanted between those of the 2 nd and 3 rd , extend to the 

 middle of the median spines and are 0,3 mm. long. The inner uropods reach backward as 

 far as there where the spines of the 4 th pair are implanted; they are fringed on both margins 



