65 



'Ihe plcon is very strong featured, its basal portiun being pro- 

 -duced into prominent submedian bosses, and tlic terminal portion 

 also having two that are even more prominent, overhanging the 

 triangular telsonic portion, the apex of which is somewhat 

 trilobed and curves upward beyond two little notches. There are 

 two tufts of setulcs on the underside of the apex, and the medio- 

 lateral parts of the pleon are setulose. The basal portion shows 

 four components, the first marked by a sinuous dorsal line, the 

 next two only by lateral sutures, but the second, third, and fourth 

 segments are much broader than the first, and the second has a 

 more extensive lateral margin than the rest, and one which out- 

 lianks the side-plate of the seventh perseon segment- 



The eyes are dark, of irregular shape, tending to oval, with 

 about a hundred small components. 



The first antennae have the first joint much longer than the 

 second and third combined, the second much narrower than the 

 first, broader but considerably shorter than the third. The 

 flagellum of nineteen joints, carrying hyaline filaments, is shorter 

 than the peduncle. The second antennae are rather longer than 

 the first^ with the penultimate joint of the peduncle not shorter 

 than the ultimate, the fifteen-jointed flagelhmi subequal in length 

 and proximally in breadth to the peduncle- 



The epistome and upper lip, as seen in situ with the other 

 ■' oris partes," and as seen when detached, are shown in the 

 figures. The mandibles are particularly massive, with the palp 

 especially inconspicuous and membranaceous. The cutting edge 

 is very dark^ and looks like a single undivided tooth, very blunt. 

 The secondary plate on the left mandible is also dark-coloured, 

 simple but comparatively thin and small ; the crown of the molar 

 is light brown in colour, so prominent and so close to the 

 secondary plate that no spine-row could be perceived between 

 them. On the right mandible the secondary plate is divided into 

 slendei" teeth. 



The lower lip has the principal lobes quadrately rounded, 

 rather strongly spinulose, their inner margins indented, the innier 

 lobes pretty strongly developed- 



The first maxill?e have the usual four plumose setse on the apex 

 of the inner plate^ these setae slightly increasing in length from 

 the outer to the innermost. On the outer plate nine horn- 

 coloured spines surmounted the apex on one maxilla, and ten on 

 the other. 



The second maxillae have w^hat I suppose to be the exopod very 

 distinctly represented by a rather long, narrow lobe of the outer 

 margin;' of the three plates, the inniermost has some plumose 

 spines mixed with the others, while on the middle and outer 

 plates there are to each about ten thin graduated spines. 



The maxillipeds have the plate arising from the se-cond joint 

 more than twice as long as broad, with the greatest breadth 



A1847. ^ 



