248 U-S. NATIONAL MUSEUM BULLETIN 23 6 



especially 2nd, which reaches % body length; 3rd is much shorter. 

 Both setae are finely haired. 



Rostrum (after dissection) proved to be triangular plate, apex pro- 

 vided with 2 movable, pointed appendages (fig. 99a). 



Antennules haplocerate, 7-segmented; 1st segment of considerable 

 size, with fuiger-shaped, denticulated process covering part of 2nd 

 segment. 2nd and 4th antennular segments each with long aesthetasc. 

 Penultimate segment with small, scale-shaped process. Setation 

 represented in figure 99a; some of setae on this complicated structure 

 may have a different insertion. In the presence of 2 aesthetascs this 

 species resembles Metis ignea Philippi. 



Antenna (fig. 99a) with short, stubby coxa and cylindrical allobasis, 

 bearing 1 internal seta. No exopodite has been observed; total 

 number of appendages on the endopodite is 7, 1 of which is a fine 

 seta. 



The oral parts are greatly reduced; the condition found in my 

 preparation of these parts resembles the condition figured by Gurney 

 (1927, figs. 166, 166 B) and Nicholls (1941a, fig. 5) so greatly that I 

 need not repeat the description here. The seta on the appendage 

 homologized by Gurney with the maxillipede has a much shorter 

 apical seta than seems to have been the case in Gurney's figured 

 specimen of Metis ignea. 



Leg 1 (fig 996) with 1-segmented, conical endopodite, and 3-seg- 

 mented exopodite. Coxa big, with external coronula of spinules, basis 

 with strong external and internal spine. Exopodal segments of nearly 

 same length, 2nd without internal seta, 3rd with total of 4 appendages, 

 increasing in size internally. Apex of endopodite does not reach 

 jointing between 2nd and 3rd exopodal segments; there is a strong, 

 internally curved spine at the middle of the internal margin, and a 

 long apical spine. In the structm-e of leg 1, especially the endopodite, 

 this specimen differs from the previously published descriptions of 

 this form. 



The details of legs 2 to 4 (figs. 99c-e) appear from the following 

 notes and the setal formula: 



Exopodites and endopodites of legs 2 to 4, 3-segmented. 



Leg 2. External spine on basis duplicated, internal seta on basis 

 near insertion of endopodite. Internal surface of 1st and 2nd endop- 

 odal segments haired (fig. 99c). 



Leg 3. Internal seta on 1st endopodal segment short and strong 

 (fig. 99c^). 



