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ment; the individual plates approach gradually to the 

 quadrate shape behind; that of the first segment projects be- 

 hind and before to an equal degree, and is deeper than the 

 others; that of the seventh is not so deep as the others. The 

 plates, being slightly excavate, show ridges on the free 

 margins. 



The sides of the anterior portion of the pleon show three 

 faint lines crowded together, marking coalesced segments ; this 

 portion is deeper than the epimera of the thorax, and its 

 anterior border carries a small tooth-like projection, usually 

 hidden by the last plate of the thorax. Posteriorly there 

 is a large median projection, which is vertically compressed, 

 and far exceeds the end of the pleon; its end is obtuse and 

 rounded. The posterior portion of the pleon bears a conical 

 tubercle on each side of the median projection of the an- 

 terior part, with two or three small granules above each, 

 and its antero-lateral parts have oblique ridges extending 

 to the insertions of the uropods. The posterior notch is ver- 

 tically excavated, moderately deep, its roof projecting be- 

 hind very slightly, and there is only the faintest indication 

 of three teeth on this. 



The first joint of the antennular peduncle is about 

 three times longer than broad; its distal end has two pro- 

 jections, the posterior one projecting outwards, the anterior 

 upwards. The second joint, which reaches out to the level 

 of the anterior end of the eye, is about one-third the length 

 of the first, and is distally bifid and 'ridged above and below; 

 the third joint, which is considerably narrower, is cylindrical, 

 and is articulated under the bifid projection of the second. 

 The flagellum has 15 or 16 joints. 



The antenna has the last two joints of the peduncle 

 subequal in length ; the flagellum is not much longer than 

 the peduncle, and consists of 18 short joints. 



The mandibles are massive, without dark tips to the 

 incisory plates, and with no distinct division into incisory 

 plates and molars, and there are no secondary plates or 

 spine rows. The palp is rather feeble. 



The spines on the outer branch of the first maxillae are 

 dark. 



The second maxillae are narrow, all the lobes reaching 

 the same distance. 



In the maxillipeds the distal end of the plate of the 

 second joint is sparingly setose; the lobes of the palp are 

 long. 



The legs are rather slender. 



In the first gnathopods the ischium is shorter than the 

 basis; the merus, carpus, and propodus are spined in the 



