128 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ili 



surface with approximately 23 plumose setae and setules, anterior 

 dorsal surface with pair of plumose setules. Second segment rodlike, 

 with approximately 12 naked setules distally. Antenna (fig. 47c) 

 3-segmented, situated posterior and medial to antennule base. First 

 segment short, squat; second segment broad proximally, tapered to 

 lightly narrower distal end, with small, horseshoe-like projection on 

 lateral anterior surface in distal half of segment. Third segment and 

 clawlike terminal process fused, single setule-like accessory process 

 present. 



Mandible (fig. 47c) 4-parted, rodlike, distalmost part curved me- 

 dially, with 12 denticulations on inner surface. Labrum with minute 

 denticulations on distal sm-face. Postantennal process (fig. 47c) 

 situated lateral to antenna base, consisting of clawlike process and 

 3 nodules, each with several hairlike processes. Postoral process 

 (fig. 47c) long, spinelike, distal end flattened slightly, appearing spade 

 shaped. Maxillule (fig. 47c) nodular, with 3 setules. Maxilla (fig. 

 47(/) 2-segmented, situated lateral and slightly posterior to postoral 

 process. First segment approximately foiu'-fifths the length of 

 second; second elongate, slightly swollen medially, with fine membrane 

 on medial swelling and 2 saber-shaped terminal processes. Inner- 

 most terminal process approximately twice length of outer, with fine 

 membrane along both margins; outer terminal process with frilled 

 membrane along outer margin. 



Maxilliped (fig. 47c) 2-segmented, situated posterior and medial to 

 maxilla base. Fu-st segment strongly developed, proximal half ta- 

 pered to narrow proximal end, curved strongly; distal half tapered to 

 irregular distal end. Second segment short, separable from claw- 

 like terminal process, bearing single setule-like accessory process 

 from distal inner surface. Sternal furca (fig. 47/) situated on median 

 longitudinal axis of body approximately halfway between maxil- 

 liped bases and first thoracic legs. Tines chisel shaped, diverging 

 slightly; furca attached to small, platelike projection. 



For nature of legs and armatiu-e, see figm'e 48 and table 17. 



DiscussioN.^ — ^The Hawaiian material differs from the original 

 description of Caligus bonito Wilson, 1905b, in one major respect, the 

 longer abdomen of C. bonito. In an examination of the type material 

 of C. bonito (USNM 6035, 41975) considerable variation was noted 

 in both the length and width of the abdomen. This variation appears 

 to be due to the maturity of the specunens. The length of the region 

 posterior to the swollen anterior portion of the abdomen of the 

 Hawaiian specimens approximates the length of the region behind 

 the slight constriction (joint between segments) of the abdomen of 

 C. bonito. Based upon this, upon the absence of egg strings in the 

 Hawaiian material (although formative strings are present in the 



