2M Pe 
Male unknown. 
This small species can readily be identified by the very narrow distal portion of the 
fifth pair of feet, and by the slender condition of the whole of the outer marginal setae. 
Occurrence. — One specimen was found in the washings from dredged invertebrata 
collected at Station 226, at a depth of 1595 metres. 
Genus Parapeltidium nov. 
The body is comparatively short and greatly depressed. The exoskeleton is highly 
chitinised. It is also strengthened with broad’ anastomosing bands of chitin. The cephalic seg- 
ment is very large and expanded. The rostrum is large and moderately prominent. The thoracic 
segments are slightly produced. The genital segment is large and strongly chitinised. The other 
abdominal segments are short. The antennules are short and five-jointed. The antennae, man- 
dibles, maxillae and second pair of maxillipedes are similar to those of Peltedium purpureum. 
The first pair of maxillipedes is similar to that of A/tewtha depressa. The terminal joint is of 
moderate length and ends in a short claw. The exopodite of the first pair of feet is slender | 
and is three-jointed. The endopodite is two-jointed, but the basal joint is not expanded as in 
Peltidium. The second, third and fourth pairs of feet are similar to those of the genus Pedéz- 
dium. The fifth pair of feet consists of a single, highly chitinised, spiniform joint. 
This genus is closely related to Pe/tzdz:wm in the possession of the anastomosing chitinous 
bands, but the whole exoskeleton is much stronger and more flattened. The slender endopodite 
of the first pair of feet and the one-jointed spiniform fifth pair, readily separate this genus 
from Peltidium. 
One species was represented in the plankton collected by the ‘Siboga’ in the Malay 
Archipelago. 
The absence of a division between the proximal and distal parts of the fifth pair of 
feet of the three genera, Lzfelte, Alteuthella and Parapeltidium, appears to be of some 
importance. This character readily separates these genera from the members of the family 
Peltidiidae, as defined by Professor G. O. Sars in ‘Crustacea of Norway’ Vol. V, page 61. It 
may be found necessary, therefore, at some future period to establish a separate family for 
their reception. 
1. Parapeltidium johnstont nov. sp. Plate LXV, figs. 1—5. 
Female — length 1,36 mm. 
Seen from above, the body appears very wide and depressed. It is oval in outline. The 
cephalic segment is large. The distal ends are expanded and are produced beyond the ends 
of the first thoracic segment. The greatest width is at the end of the cephalic segment and 
is equal to two-thirds of the entire length of the animal. The distal ends of the cephalic and 
thoracic segments are pointed. The segments are produced dorsally in the middle line into 
triangular projections. The rostrum is moderately large and prominent. The frontal margin is 
truncate. The genital segment is large and is deeply indented in the middle. The distal ends 
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