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PROCEEDINGS OF THE NATIONAL MUSEUM 



The character of the membranes, spines, and setae on the thoracic 

 legs is given below (for explanation of symbols, see figure 1): 



Caudal rami of female and male slightly wider than long, greatest 

 length, excluding setae, about one-tenth length of female genital seg- 

 ment. Rami bearing sLx plumose setae; three long setae present on 

 distal margin, short seta from each distal lateral corner, short seta 

 from median distal ventral sm'face (fig. 4c). 



Remarks. — This species is similar to Caligus oviceps Shiino, 1952, 

 in the possession of flexible terminal processes on the fii"st thoracic 

 leg and in other tlioracic leg characteristics. C. flexispina differs 

 from this species in the possession of a fom'th process, a naked seta, 

 on the distal end of the first thoracic leg. In addition, C. flexispina 

 possesses a distinctly separated fourth thoracic leg-bearing segment 

 in both sexes and a distinct two-segmented abdomen in the male, 

 while the fourth thoracic leg-bearing segment and genital segment 

 in the female of C. oviceps are fused and in the male the division of 

 the abdomen is incomplete. O. oviceps also possesses a four-segmented 

 fourth thoracic leg while C. flexispina has a three-segmented fourth 

 leg. 



The name "flexispina" refers to the flexible terminal processes of 

 the first thoracic leg. 



Caligus randalli, new species 



Figures 6a,b,d-f,h-l,n-q,7a-d 



Material. — Ovigerous female (holotype, USNM 105102) collected 

 by Dr. John Randall from epidermis of specimen of Acanthurus tri- 

 ostegus sandvicensis Streets, captured in unknown locality on Oahu, 

 Hawaii. 



Measurements. — Length from anterior end to posterior end of 

 caudal rami, excluding setae, 4.14 mm. Greatest length of cephalo- 



