REPORT ON THE SCIHIZOPODA. 49 



to work='out the specific c.hameters satisfactorily, as also to give correct figures of the 

 general appearance and fcjrm of the body. The specimen has not a trace of incubatory 

 lamellae, and hence is most likeh^ a male. Its length is only 4f mm. 



The form of the liody (figs. 6, 7), as compared with the other species of the genus, 

 is very slender, for which reason the late Dr. v. Willemoes-Suhm suggested the specific 

 denomination " gracilis." 



The carapace is comparatively small, and does not seem to cover completely the last 

 segment of the trunk. It projects posteriorly into a well marked, although rather short, 

 <lorsal spine, scarcely reaching Ijeyond the first caudal segment. The infero-posterior 

 corners of the carapace, instead of being rounded off, as in the species belonging to the 

 second section, are somewhat prominent, and jut out into two posteriorly directed spines, 

 of somewhat unecpal length, the lower rather short, whereas the upper attains about the 

 length of the dorsal spine. Of the lateral keels, the lower only is distinctly developed, 

 and it runs parallel to the inferior margin of the carapace, terminating at the base of the 

 upper spine, which issues from the infero-posterior corner. Of the upper lateral keels, on 

 the other hand, no trace whatever can lie discerned. The dorsal keel is interrupted in 

 the anterior part of the carapace, where a distinct transverse impression is seen to occur, 

 apparently corresponding to the cervical sulcus in other Schizopoda. In the posterior 

 part, however, the keel is well marked, and armed with a row of strong, anteriorly 

 curving denticles. The rostrum is rather elongate and slender, about as long as the 

 carapace, and, as in the other species, three-edged, being also armed with strong denticles, 

 <'ontinued along the dorsal edge to some distance posterior to the base of the rostrum. 

 The supra-orbital sjjines are very small, and not distinctly defined from the base of the 

 rostrum, being placed somewhat anterior to the insertion of the eyes. Tlie antennal 

 spines are well marked, though not very large. On the other hand, the branchiostegal 

 spines are enormously developed, and project on either side as strong wing-like exj)ansions, 

 tapering to a sharp point. 



The caudal segments are rather slender, and the five anterior ones are armed with 

 dorsal projections, those on the two foremost being distinguished by their exceedingly 

 large size. On the second segment occur two such projections, of an acutely triangular 

 form, both placed in the middle line, and pointing the one posteriorly, the other anteriorly. 

 On the first segment may also be observed two projections, of which, however, the 

 anterior is very small, whereas the laosterior is rather large, and points straight upward. 

 ( )n the other segments, only a small projection is seen in the middle of the posterior 

 margin. The epimeral plates issuing from the anterior section of the last segment are, as 

 in G aathophausia longispina, armed with two small denticles. 



The eyes are very small and narrow, the cornea being scarcely exjianded, and ouh- 

 occupying the outermost extremity of the eye. 



The antennulae do not seem to exhil)it any essential difference from those in other 



(ZOJL. CHALL. EXP. PART XXXVII. 1885.) ()0 7 



