50 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



Female free fourth pedigerous segment, excluding alae, slightly 

 more than one-fifth the width of cephalothorax, widest medially, at 

 attachment of fourth thoracic legs. Alae wddest anteriorly, con- 

 stricted medially, broadly rounded posteriorly, covering anterior third 

 of genital segment. 



Female genital segment (fig. 19c^) broadly rounded anteriorly, 

 lateral margins flatly convex, lateral-posterior dorsal surface extending 

 posteriorly as pair of lobate projections, projections not distinct 

 from genital segment. Dorsal surface of genital segment platelike, 

 extending laterally past somewhat irregular posterior ventral surface. 

 Fifth legs (fig. 19/) arising from ventral lateral surface of platelike pro- 

 jection of dorsal surface of genital segment, consisting of pair of nod- 

 ules, anteriormost -with single setule, posterior with 3 setules. Ovoid, 

 adhesion-like surface present just posterior to fifth legs. 



Female abdomen 2-segmented, distinct from genital segment. 

 First segment slightly shorter than second, broader anteriorly than 

 posteriorly, w4th slight posterior lateral projections; second segment 

 with convex lateral margins and slight, bilobed, anal projection. 

 Caudal rami broad, with 4 plumose setae and 2 naked or very lightly 

 plumose setules from distal surface, \\ath row of fine denticulations 

 around base of outermost seta. 



Male cephalothorax (fig. 196) similar to that of female although 

 somewhat narrower, mthout dorsal plumosities or distinct projections 

 indicating previous presence. Free fourth pedigerous segment more 

 drawn out medially than in female, alae not as large, wdthout medial 

 constriction present in female. Genital segment (fig. 19e) basically 

 ovoid, without platelike dorsal part and posterior extensions of female; 

 fifth leg (fig. 19^) similar to that of female, genital segment \\dthout 

 adhesion-like surface present in female. Abdomen 2-segmented, 

 first segment slightly shorter than second, overlapping second dorsally ; 

 second segment tapered anteriorly, with flatly convex lateral margins 

 and bilobed anal projection. Caudal rami as in female although 

 more plumose along inner margin. 



Female and male antennule (fig. 20a) 2-segmented, most of anterior 

 surface of first segment overlapped by ventrally curved lateral surface 

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

 of second, broad proximally, tapered irregularly to narrow distal end, 

 with smafl, knoblike projection from posterior distal surface, with 15 

 naked or lightly plumose setules from anterior ventral and distal 

 ventral surfaces in female, male with 19 naked or lightly plumose 

 setules. Second segment subrectangular, ^\ith 1 naked setule from 

 median dorsal surface, second from distal posterior surface, and 8 or 9 

 naked setules from distal surface. Female antenna (fig. 20b) 3-seg- 

 mented, situated medial and posterior to antennule base. First 



