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PROCEEDINGS OF THE NATIONAL MUSEUM 



processes. Innermost terminal process approximately Iji times the 

 length of outermost, both with fine membranes along margins. 



Female and male maxilliped (fig. 586) 2-segmented, situated pos- 

 terior and slightly medial to base of maxilla. First segment strongly 

 developed, with distally concave ledge on inner siu-face that receives 

 tip of terminal process of second segment when segment flexed. Sec- 

 ond segment distinct from clawlike terminal process, with single, 

 setulelike accessory process on distal inner surface. Female and male 

 sternal furca (fig. 58/) situated approximately halfway between max- 

 illiped bases and interpodal plate of first thoracic legs, on small, 

 heavily sclerotized platelike region projecting laterally as 2 small 

 lobate processes, adjacent to base of furca. Furcal tines diverging, 

 sinus irregularly V-shaped, tines broad, fiat. 



Spine at distal end of &st segment of exopodite of third thoracic 

 leg straight, not curved. For nature and armature of legs, see figure 

 59 and table 21. 



'Division between second and third segments of exopodite indistinct, incomplete. 



Discussion. — Caligus kapuhili exhibits several chai'acteristics closely 

 approximating those of C. laticaudus Shiino, 1960a. The similarity 

 of the lunule, the female and male antenna (male C. laticaudus de- 

 cribed by Pillai, 1961), the maxilliped with its cup-shaped projection 

 on the first segment, and the similarity of the first 3 thoracic legs 

 suggest that these 2 species are closely related. The differences 

 between the species are in the body shape, the size relationship of 

 the body parts, and the characteristics of the appendages other than 

 those mentioned above. Shiino's female and only specimen of C. 

 laticaudus is reportedly 3.51 mm in length. Pillai reports a length 

 of 2.6 mm for his female specimens (no length given for the male), 

 the average length of the Hawaiian female specimens is 1.94mm, 

 and the range is from 1.67-2. 37mm. The abdomen is distinctly 

 2-segmented in C. laticaudus and 1-segmented in C. kajnihili, while 

 its length (female only) is 0.71mm in C. laticaudus and an average 



