138 TJ.S. NATIONAL MUSEUM BULLETIN 236 



base is curved and curve fits perfectly into outline of cephalon; its 

 true presence readily discovered in lateral aspect (fig. 49a). 



Antennules 6-segmentcd, reduction resulting apparently from fusion 

 of 4th and 5th segments, which still have partly developed jointing at 

 internal side. Setation of antennule represented in figure 496; aesthetascs 

 occur on 3rd and 4th free segments. 



Antenna (fig. 506) as in Peltidium intermedium, but with differently 

 shaped setae on endopodite. On exopodite there is no lancet-shaped 

 seta, but one of the apical setae is strong. 



Cutting edge of mandibular praecoxa with small teeth and fine 

 basal seta. Structure appears in figure 49c. Palp as in P. intermedium. 



Maxillule as in preceding species, not described in detail. 



Maxilla differing from that of P. intermedium in structure of coxal 

 endite, which has 3 appendages: fine seta, seta with thickened base, 

 and flattened dagger-shaped spine (fig. 49rf). 



Maxillipede (fig. 49e) with strongly swollen basis, with row of 

 spinules along internal margin; no ciu^ved spine at that margin as in 

 preceding form. Endopodite short, 1-segmented, curved process, 

 reaching % length of basis, without setae. 



Leg 1 (fig. 50c) with internal, spinulose lamella along external 

 margin, internal margin haired. Strongly thickened trabecle in coxa. 

 Basis with internal and external seta and socle bearing 3-segmented 

 exopodite; endopodite 2-segmented. 1st exopodal segment with 

 external seta; 2nd exopodal segment twice length of 1st, with internal 

 and external seta. 3rd exopodal segment small, with 2 small external 

 claws and 2 big, strongly curved spines of unequal size at apex. 

 Endopodal segments of same length, 1st with strongly plumose internal 

 seta. Four appendages on 2nd endopodal segment: 2 apical setae and 

 2 internal setiform spines with broadly curved lamella, composed of 

 closely adpressed hairs and very transparent, with the result that this 

 structm-e easily is overlooked in unstained preparations. 



Legs 2 to 4 (figs. 50d~J) almost as in P. intermedium, with the 

 following setal formula: 



Leg 5 with greatly lengthened external lobe of baso-endopodite, 

 reaching distal third of exopodite, with fine seta. Baso-endopodite 

 small, almost vestigial, with strong seta and fine hahlike seta. 

 Exopodite 4 times as long as broad, with 5 marginal setae: 3 (2 fine, 1 

 strong) at apex and 2 strong setae at internal margin (fig. 49/). 



Remarks. — -The present specimens show perfect agreement with A. 

 Scott's description and figures except for the structure of the 2nd 



