18 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 125 
side although nodules not always in row. Fifth leg (fig. 9e) situated 
on lateral ventral surface in posterior half of segment, consisting of 
palp bearing 4 plumose setules, Abdomen 1-segmented, distinctly 
separable from genital segment. Lateral margins, in adult, irregular, 
anterior surface broader than posterior. Posterior surface flat laterally, 
broadly bilobed medially, junction of lobes forming anal indentation. 
Caudal rami (fig. 7f) small, subrectangular, with 3 plumose terminal 
setae, 1 plumose setule on inner distal surface, and plumose seta and 
setule on proximal lateral surface. 
Male cephalothorax and free pedigerous segments similar to those 
of female (fig. 7a). Genital segment (fig. 7c) elongate, rounded an- 
tt tt 
a | O41 mm. 9 
O1 mmc 
Figure 8.—Dissonus heronensis Kabata, 1966, ventral views: a, female oral region, showing 
antenna, mouth cone, mandible, maxillule, maxilla base (ma-—2), postantennal process 
and postoral process; b, male left antenna and postantennal process; ¢c, right maxilla; 
d, male left maxilliped; ¢, female left maxilliped. 
