185 
second joint of the left basiopodite apparently does not possess the strong spine that is 
present in the ‘Siboga’ male, and no reference is made to the long outer edge spine on the 
second joint of the exopodite of the second pair of feet. 
Occurrence. — Two females and one male were obtained from the plankton collected 
with the HeEnsen vertical net at Station 143, 1000 metres to the surface. 
Genus Neopontella nov. 
This genus is very closely related to Parapontel/a, and at first sight I was inclined to 
regard its representative to be a true member of that genus. A closer examination of the two 
sexes, however, shewed that it is clearly distinct. 
The generic differences between this genus and Parafontella, are in the structure of 
the fifth pair of feet of the female, and in the segmentation of the abdomen of the male. 
The female fifth pair of feet has no trace of an endopodite. The abdomen of the male 
is composed of four segments. 
The antennules, antennae, mandibles, maxillae and maxillipedes are almost identical 
with those of Parapontella brevicornis (Lubbock). The four pairs of swimming feet are also 
similar to those of that species. 
One species belonging to this new genus was obtained from the plankton collected 
during the traverse of the ‘Siboga’. 
1. WMeopontella typica nov. sp. Plate LV, figs. 1—15. 
Female — length 1,13 mm. 
Seen from above, the body appears elongate ovate in outline. The greatest width is 
in the middle. The width is contained two and a half times in the total length of the body. 
The head is distinctly separated from the first thoracic segment. The frontal margin is rather 
broadly rounded. The fourth and fifth thoracic segments are completely fused. The last thoracic 
segment is very slightly produced. The posterior margin of the segment is narrowly rounded. 
Viewed from the side, the apex of the last thoracic segment is seen to be evenly and rather 
bluntly rounded. The rostrum is almost similar to that of Parapontella brevicornes, but the 
filaments appear to be rather shorter (Plate LV, fig. 3). 
The abdomen is composed of three segments. The combined length of the abdomen 
and furca is contained fully twice in the total length of the cephalothorax, from the frontal 
margin to the base of the genital segment. The genital segment is considerably swollen. It is 
nearly equal to the combined length of the next two segments. Seen from the side, the segment 
appears greatly inflated in the region of the genital opening. The second and third segments 
are of nearly equal length. The second segment is not armed with spines. The furcal joints 
are nearly twice as long as broad, and are almost as long as the anal segment (Plate LV, 
mess i atid) 2): 
The antennules are composed of eighteen joints. The third and fourth joints are very 
small. The last joint is indistinctly segmented at the distal end. 
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