than in the male (fig. 5/); its widened basal part with two pairs of ver y strong spines; the end 

 is broadly rounded with 3 small spines at the middle and two pairs of long spines, the outer 

 pair somewhat longer than the inner; the spines along the distal third of its lateral margins 

 do not increase quite regularly in length towards the end, yet much more regularly than in 

 5". cequiremis, S. inornata or allied forms, only the 3 last spines increase always regularly but 

 rapidly and are closely set, while the others generally are distant from each other, varying 

 considerably in length and arranged so that 2, 3 or 4 spines increase in length posteriorly, 

 and then comes again a short spine; besides the lateral spines of the distal half differ from 

 those in the following species excepting S. nodosa in being less numerous and, with exception 

 of the distal ones, less closely set, some of the intervals being as long as, or considerably 

 longer than, the preceding spines. 



Length of the male 7 mm., of the female 6.5 mm. 



Remarks. — This species is easily distinguished from all following forms by the 

 armature of the telson ; from the two preceding species it is separated by having the endopod 

 of the uropods shorter than the exopod. — A female without marsupium from Stat. 66 has 

 an enormous Epicarid, probably a species of Notophryxus, on the upper side of the carapace. 



15. Siriella nodosa n. sp. PI. III, figs. \a — 1 /. 



Stat. 129. July 22/23. Anchorage off" Kawio- and Kamboling-islands, Karkaralong-group. 23-31 m. 

 Plankton. 5 specimens. 



Description. — The body a little more clumsy than in allied forms. Frontal plate 

 of the carapace (fig. 1 a) in both sexes considerably produced, triangular, with the tip narrowly 

 rounded; in the female the cephalothorax has in the median line two, seen from the side (fig. 1^) 

 obliquely triangular, protuberances, one just in front of the cervical groove, the other a little 

 behind the middle; these protuberances are wanting in the male. Eyes moderately large, dark 

 reddish. Antennular peduncle in the male thicker than in the other species. Antennal squama 

 (fig. 1 c) subequal in both sexes, three times as long as broad ; terminal lobe very short, slightly 

 overreaching the tip of the marginal denticle. Gnathopods (fig. 1 d) considerably shorter than the 

 somewhat slender first pair of thoracic legs, and the thoracic legs increase very much in length 

 from first (fig. 1 c ) to third pair (fig. 1^-), the third pair being nearly two and a half times as long 

 as the gnathopods and two-thirds as long again as first pair; fourth to sixth pairs again somewhat 

 shorter; it has been impossible to discover any secondary articulation of the sixth joint on any 

 of the legs. Male pleopods and pseudobranchial rami as described in the definition of the group. 



Uropods (figs. ik and \i) with the exopod scarcely or slightly overreaching the endopod; 

 the rami are broad in the female (fig. 1//), conspicuously narrower in the male (fig. iz); the 

 exopod has only 3 or 4 marginal spines, and its distal joint is about half as long again as 

 broad. In the female the telson (figs. ik and 11) is broad and proportionately short, less than 

 twice as long as broad, not reaching the articulation of the exopod, and considerably less than 

 half of its lateral margins is set with spines; in the male the telson (fig. ik) is longer and much 

 narrower than in the female, reaching somewhat beyond the articulation of the exopod, and 



SIBOGA-EXrEDITIE XXXVII. 5 



