204 



of the cephalic and thoracic segments are pointed. The segments are produced dorsally in the 

 middle line into triangular projections. The rostrum is large and prominent. The frontal margin is 

 truncate. The genital segment is large and much produced posteriorly. The distal ends of the 

 genital segment extend to about the middle of the furcal joints. The furcal joints are three times 

 longer than broad. The outer margin of the joints is not furnished with a seta (Plate LXV, fig. 6). 



The antennules are composed of seven joints. The fifth ancl sixth joints are very small. 



The antennae, mandibles, maxillae and maxillipedes are similar to those of the previous 

 species. 



The exopodite of the first pair of feet is slender. The first joint is distinctly longer than 

 the second joint. The third joint is very short. It is armed with one stout ancl one slender 

 curved claw. The endopodite is much shorter than the exopodite. The joints are of nearly 

 equal length, but the first joint is wider than the second joint. The apex of the second joint 

 is furnished with two pointed spines and two seta (Plate LXV, fig. 9). 



The second, third and fourth pairs of feet are similar to those of Pcltidium purpureum. 



The fifth pair of feet is moderately stout. The second joint is furnished with two outer 

 edge setae, two apical setae, and one inner edge seta (Plate LXV, fig. 10). 



Male unknown. 



This species can readily be separated from the other members of the genus by the 

 comparatively slender furcal joints which have no median outer marginal seta, and by the 

 arrangement of the setae on the fifth pair of feet. 



Occurrence. - - One specimen was found in the surface plankton collected at Station 

 2 1 3, Saleyer Island. 



3. Pcltidium exiguum nov. sp. Plate LXV, figs. 11 — 15. 



Female — length .98 mm. 



Seen from above, the body appears moderately broad and rather depressed. It is oblong 

 ovate in outline. The greatest width is at the distal end of the cephalic segment and is equal 

 to rather less than half the length of the entire animal. The distal ends of the cephalic and 

 thoracic segments are pointed. The segments are produced dorsally in the median line into 

 triangular projections. The rostrum is rather wide but it is not very prominent. The frontal 

 margin is broadly rounded. The genital segment is large and broad. The pointed distal ends 

 of the segment scarcely reach to the end of the anal segment. The furcal joints are moderately 

 broad and fully twice as long as wide. The middle of the outer margin of the joints is furnished 

 with a short seta (Plate LXV, fig. 11). 



The antennules are composed of six joints. The fifth joint is very small. 



The antennae, mandibles, maxillae and maxillipedes are similar to those of Pcltidium 

 intermedium. The terminal claw on the second joint of the second pair of maxillipedes is 

 comparatively stout and is blunt pointed. 



The exopodite of the first pair of feet is moderately stout. The first and second joints 

 are of nearly equal length. The third joint is very small and is furnished with three curved 

 claws. The outer one is smaller than the others. The middle claw is comparatively stout. The 



204 



