172 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



Antennule (fig. 65c) 3-segmented, attached to concave frontal 

 projection, immediately anterior and slightly lateral to labriim. 

 Appendage flaccid, first segment broad proximally, approximately 

 half as wide distally, with flexible, subconical projection on inner 

 surface. Second segment short, approximately two-thirds the 

 length of third segment; third segment rounded distally, distal sur- 

 face with 2 setules. Antennae (fig. Q5d) large, biramous, attached 

 lateral and slightly posterior to antennule. Protopodite subrec- 

 tangular, with irregular areas of heavy sclerotization. Exopodite 

 separable from distal surface of protopodite by breaks in scle- 

 rotization, with 2 minute, knoblike projections on inner part of 

 rounded distal surface; entire ramus, including projections, covered 

 by filmy cuticle. Endopodite distinctly separable from distal inner 

 siu-face of protopodite, apparently 3-segmented although status of 

 terminal "segment" questionable. First and second segments sub- 

 cylindrical, first slightly less than twice the length of second. Third 

 "segment" approximately two-thirds the length of second, concave 

 distally, with minute, setule-like projection arising from concavity. 



Mandible (fig. Q5d) rodlike, distal end flattened, inner edge rounded, 

 without apparent denticulations. Maxillule (fig. 65e) situated 

 adjacent to posterior lateral edge of mouth cone base, consisting 

 of stalk with palp on distal half of inner siu"f ace, palp tipped by spine- 

 like projection. Distal end of maxillule rounded, with single short, 

 setalike process on outer edge, 2 long, setalike processes on medial 

 and inner edge. Maxillae (fig. 65a) subcylindrical, flabby, distal 

 region (fig. 65/) tapered to bulbous swelling formed by convolution 

 of distal end of each maxUla; swellings enclosing tip of capstan- 

 shaped bulla. 



Maxilliped (fig. 65^) 2-segmented, situated posterior and medial 

 to maxillule base, arising from small, apron-shaped projection of 

 ventral surface of cephalothorax. Fii'st segment well developed, 

 approximately twice the length of second, medial inner surface with 

 knob-shaped swelling bearing small, conical projection. Second 

 segment Avith wavy outline, distal third of inner surface denticulated, 

 inner distal surface bearing setalike process. Terminal process of 

 second segment originating on outer distal surface of segment, claw- 

 like except for spike-shaped accessory projection on medial inner 

 surface. 



Discussion. — The Hawaiian specunens differ from Wilson's type- 

 material (USNM 64009-64011) and Pearse's holotype and paratype 

 slides (USNM 92663, 92688) in size, the Gulf of Mexico specimens 

 being approximately f om'-fif ths the length of the Hawaiian specimens 

 (excluding posterior processes). There is also some minor variation 

 in the size and shape of the various body regions and posterior proc- 



