REPORT ON THE SCllIZoruDA. 207 



The in;ixilli2>eds (fig. 12) are more pediform than in most other Mysidans, tlie basal 

 sectiou being comparatively short, whereas the terminal part, or endopodite, is rather 

 l)roduced. The cpipodite is comparatively .small, and cxiiibits the nsnal lanceolate form 

 and membranovis structure. 



The gnathopoda (fig. 13) are still more pediform, hut lathcr smaller than the true 

 legs, from which they moreover difler in the terminal j<iiut liting not unguiform but 

 lamellar, and. armed with numerous slender spines. 



The true legs (figs. 14, 16) are comparatively less feeble in structure than in most 

 other Mysidans, and more decidedly ambulatory in their character, the propodal joint 

 being not multiarticulate and flexible, but C[uite rigid, and in the present species appa- 

 rently undivided, whereas in the other species a short proximal articulation may be 

 distinguished. From the tip of the propodal joint a double row of densely crowded and 

 very delicate, finely serrate bristles are seen to spring, forming a dense fascicle, between 

 which the terminal joint projects (see fig. 1 5). The latter has the form of a strong falciform 

 claw, resembling that in the higher forms of Macrurans. The posterior pair of legs (fig. 16) 

 are somewhat smaller and more slender than the rest, especially in the male, but do not 

 difler in structure. In all the legs, and likewise in the maxillipeds and gnathopoda, the 

 exopods are powerfully developed, with the basal part expanded and muscular, the 

 terminal i)art consisting of about ten short setiferous articulations. 



The marsupial pouch in the female is, as in the other species of the genus, composed 

 of three pairs of incubatory lamellae, of which, however, the anterior pair are ver}" small. 



The sexual appendages of the male (fig. 17) are comparatively small, and anteriorly 

 have three strong ciliate setae, the tip, moreover, being provided with a transverse row 

 of short curved bristles. 



The caudal limbs in the female (fig. 2) exhibit the rudimentary structure character- 

 istic of the family. In the male (fig. 1), however, they are all strongly developed and 

 natatory, with a broad muscular part, and multiarticulate setiferous branches, being 

 moreover highly distinguished by the peculiar gill-like appendage originating at the base 

 of the inner branch. This appendage, which undoubtedly corresponds to the simple 

 lamellar expansion met with here in other male Mysidans, is divided into two cylindrical 

 stems of a quite gill-like sti'ucture, and iu the middle pairs (see figs, li), 21) these stems 

 are coiled up spirally, whereas in the first (figs. 18, 20) and la.st paii- they are well-nigh 

 straight. In the first pair, as usual, the terminal part of the inner branch is wholly 

 wanting, this branch being exclusively represented by the above-mentioned appendage 

 (see fig. 18). The fourth pau', which in male Mysidans generally exhibit some modifi- 

 cation of the outer brancli, would not seem to difler in any respect from the preceding pair. 



The telson (fig. 22) is about as long as the two preceding segments taken together, 

 and remarkably narrow, being considerably constricted in front of the middle, with the 

 outer part almost linear and distinctly channelled along the dorsal face. The lateral 



