32 THE VOYAGE OF H.M.S. CHALLENGER. 



are distiuctly developed uud almost perpeudicular, projecting into two acutely pointed 

 lappets, of which the posterior is the larger and is provided with an elevated keel. 



The last segment, as in the other species, is divided by an obli(]uel)- transverse 

 suture into two sections, the anterior of which juts out on either side into an epimeral 

 projection, which unites on the ventral face with the corresponding one on the opposite 

 side, forming together a large cordiform j^late, concave in the middle and cleft at the 

 apex into two slender, bideutate lappets, reaching even somewhat beyond the extremity 

 of the segment (see fig. 6). 



The eyes (fig. 3) are more especially distinguished by the considerable length of 

 the pedicles, which are very narrow, and apparently consist of two segments, the external 

 one exhibiting above a small papillary projection. The cornea is rather expanded and 

 somewhat oblique, occupying, however, Ijut a comj^aratively small part of the eye itself 



The antennular peduncle (see figs. 1 and 2) is very short and thick, scarcely reaching 

 beyond the eyes when they are extended. The flagella, too, were partly defective in 

 the specimen examined. 



The autennal scale (see fig. 4) is comparatively very small and of an oval form, the 

 extremity being truncated or very slightly emarginate, with the inner corner a little 

 more prominent than the outer. The outer edge is somewhat arched, and, in its distal 

 half, armed wdth about six very small and inconspicuous teeth. The inner edge, too, 

 is almost straight, being rather strongly arched in its hindmost part; it is fringed 

 throughout with a dense row of comparatively short bristles. 



The oral parts, so fiir at least as they admit of l)eing examined without dissection, 

 would seem on the whole to agree perfectly with those in the two succeeding species. 

 As in the latter, the maxillipeds are provided with a distinct though very small lamelli- 

 form exopodite. 



The legs (fig. 5) are com^taratively rather robust in structure and densely setigerous 

 on both margins, the carpal and propodal joints being strongly compressed and the 

 dactylus rather small. 



The incubatory lamellge, composing the marsupial pouch, are, in the specimen treated 

 of here, exceedingly large, of an oblong-ovate form, and densely setose at the edges, 

 forming together a very conspicuous, convex prominence beneath the trunk (see fig. 1). 



The telson (see fig. 7) is very large and massive, equalling in length the three 

 preceding segments taken together. The outer part tapers successively toward the apex, 

 and has the lateral edges but slightly arched and j^rmcd with a vast nundjcr of fine 

 spinules. The two falciform apical spines are, as usual, confluent at the base, forming 

 together a semilunar projection appended to the apex of the telson, with its posterior 

 concave margin finely serrate. 



The uropoda {ibid.) are much shorter than]_the telson, but otherwise exhibit the 

 structure characteristic of the genus. 



