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PROCEEDINGS OF THE NATIONAL MUSEUM 



and second segment; second, distal, part of process directed inward 

 at right angles to first. Second segment of exopodite flattened 

 distally, lateral margins broadly rounded ; third segment almost semi- 

 circular, lateral and distal margins continuous. Endopodite two- 

 segmented; first segment broad; proximal margin of segment, as well 

 as that of first exopodite segment, indistinct. Second segment of 

 endopodite broadly rounded, distal and lateral margins distinct 

 (fig. 12o). 



Fourth thoracic leg uniramous, four-segmented. Protopodite one- 

 segmented, with small, bilobed articular surface projecting sUghtly 

 from inner proximal margin. Exopodite three-segmented, total length 

 slightly more than that of protopodite. First segment of exopodite 

 with single spine on outer distal corner; inner margin of spine 

 with indistinct, frUled membrane. Second segment with larger spine 

 on outer distal corner; spine with distinct, frilled membrane 

 along inner and outer margins, base of spine encircled by minute, 

 stiff setules. Third segment terminating in broad surface bearing 

 three spines. Outermost spine shortest, about half length of middle 

 spine, with frilled membrane along inner and outer margins. Middle 

 spine slightly shorter than inner spine, with frilled membrane along 

 outer margin only. Inner spine with few, fine setules on inner distal 

 margin. All three terminal spines encircled by minute, stiff setules 

 (fig. \2p). 



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

 legs is given below. The thoracic legs of both sexes are identical. 

 (For explanation of symbols, see figure 1.) 



Caudal ramus of female and male similar, width and length about 

 equal. Inner lateral margin setulif erous ; six plumose setae present on 

 distal and distal lateral surfaces. Innermost seta small, less than 

 one-fifth length of longest seta; three long setae from median distal 

 margin, small seta present between these three and single seta from 

 outer distal lateral margin (fig. 12r). 



