46 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



segment. Second segment convex laterally, flat posteriorly except 

 for slight, bilobed anal projection. Caudal rami broad, with 4 plu- 

 mose setae and 2 lightly plumose setules distally, with row of fine 

 denticulations around base of outermost seta. 



Male cephalothorax (fig. 166) similar to that of female although 

 lateral indentations more distinct. Alae on free fourth pedigerous 

 segment tapered laterally, without sharp constriction present in 

 female. Genital segment (fig. 16e) with flatly convex lateral margins 

 anteriorly, almost straight lateral margins posteriorly. Fifth legs 

 (fig. 16g) similar to those of female except posteriormost nodule with 

 2 lightly plumose setules instead of 3. Abdomen 2-segmented, first 

 segment narrow anteriorly, angled to widest point medially, lateral 

 margins straight posteriorly. Second segment and caudal rami 

 similar to that in female. 



Female and male antennule (fig. 17a) 2-segmented, attached to 

 anterior-lateral ventral surface of cephalothorax and adjacent portion 

 of frontal region. First segment slightly less than twice the length 

 of second, tapered distally, bearing 23 naked or lightly plumose setae 

 and setides on distal half of anterior ventral surface and distal ven- 

 tral surface. Second segment club shaped, with 14 naked setules 

 distally. Female antenna (fig. 176) 3-segmented, situated posterior 

 and medial to antennule base. First segment short, irregular, with 

 well-developed, posteriorly projecting spine from lateral posterior 

 surface. Second segment broader proximally than distally, with 

 minute setule on distal inner surface (not figured) ; third segment 

 fused with clawlike terminal process, bearing flabby, setalike accessory 

 process proximally, more elongate, setalike accessory process from 

 median third, at break in sclerotization suggesting point of fusion of 

 segment and terminal process. Male antenna (fig. 17c) similar to 

 that of female although projection on first segment shorter, with sec- 

 ondary claw on terminal process of third segment. 



Female and male mandible (fig. 176) rodlike, jointed in proximal 

 medial region, proximal portion tapered to joint, distal part flattened 

 distally, with indistinct break at beginning of flattened part; flattened 

 region ciu-ved inward, with 12 denticulations along inner margin Fe- 

 male and male postantennal process (fig. 176) consisting of 2 nodules, 

 each bearing several hairlike projections. Female and male postoral 

 process (fig. 176) broadly based, distally slender, spinelike, curving 

 laterally distally. Maxillule (fig. 176) situated lateral to mouth cone 

 base, immediately anterior to postoral process, consisting of node bear- 

 ing naked seta and 2 naked setules. Maxilla (fig. 17 d) 2-segmented, 

 situated lateral and slightly posterior to postoral process. First 

 segment slightly less than four-fifths the length of second, excluding 

 terminal processes. Second segment elongate, broadest medially. 



