Sessile-ei/ed Crusfaceanf!. 329 



carapace, that is, the head with the first perteon-segment, is 

 nearly twice as long as the greatest breadth j the front part is 

 narrowed. The tirst free segment of the peraion is shorter 

 tlian the rest, the next four being subequal, and the last only 

 a little longer than the first. The fifth segment of the pleon 

 is rather longer than any of the preceding four. The last 

 segment is rather longer than the fourth and fifth together, 

 and is obtusely rounded at the slightly narrowed extremity. 



No eyes are perceptible. The upper antennaB (of the 

 female) are shorter than the carapace ; the tirst joint much 

 longer than the next two together, the third a little longer 

 than the second, the fourth quite rudimentary. The lower 

 antennas are much smaller than and implanted considerably 

 behind the upper pair : the antepenultimate joint is much the 

 longest and carved in lateral view. 



The upper lip is dome-shajied. The mandibles have a 

 finely serrate cutting-edge combined with a couple of teeth, 

 which are stronger on the left than on the right mandible. 

 Tlie latter is shown in the figure interlocked between the two 

 teeth of the left mandible. As they are seen from below the 

 right mandible is on the left hand. 



The first maxilla consists of a long narrow lobe, curved at 

 the extremity, where it carries five seta?, with a setule on the 

 outer margin a (iitle below the apex ; the exopod was not 

 observed, but was doubtless of the usual form. 



The maxillipeds have four strong set£e on the terminal joint 

 and two smaller ones on the inner margin of the long penul- 

 timate joint. The central plate appeared to be undivided, but 

 was not clearly observed. 



The first gnathopods have the first free joint massive, 

 larger than any of the others, widest near the base, as wide as 

 long; the second joint is absent or coalesced; the third is 

 small and triangular, carrying a single setule ; the wrist is 

 more than once and a half as long as broad ; the hand proxi- 

 nially is fully as broad as the wrist, the outer margin very 

 convex, its apex projecting much beyond the base of the 

 finger, and there s-^t with several tubercles ; on the imicr side 

 it makes an abrupt bend at a very short distance from the 

 wrist, forming a broad thumb ending in a nail-like process, 

 and carrying two setai on the inner margin and three or four 

 together with some flattened tubercles on the border facing 

 the finger. The finger is irregularly tubercled on the outer 

 margin and smooth on the inner, its tip closing within the 

 unguicular process of the hand. 



The second gnathopods have the first free joint long, 

 slender, and bent ; the third, fourth, and fifth joints are sub- 

 Aun. & Mag. A'. Hist. Ser. 6. Vol viii. 22 



