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The abdomen is composed of four segments. The genital segment is large. It is much 
contracted in the distal half, which is separated from the anterior portion by a distinct suture 
traversing the dorsal surface of the segment. The second, third and fourth segments are com- 
paratively short. The furcal joints are one and a half times longer than broad (Plate LXIII, 
fig. 24). 
The antennules are moderately long and slender and are eight-jointed. The last four 
joints are narrower and shorter than the first four joints (Plate LXIII, ioe 16): 
The exopodite of the antennae is rather long and slender, and one-jointed. It is furnished 
with one strong apical seta and one slender marginal seta (Plate LXIII, fig. 17). 
The mandibles, maxillae and maxillipedes are nearly similar to those of Dactylopodella 
fiava (Claus). 
The exopodite of the first pair of feet is three-jointed. The endopodite is two-jointed. 
The first joint of the endopodite is moderately wide and is nearly as long as the combined 
length of the joints of the exopodite. The second joint is short. The apex is furnished with a 
long slender, slightly curved claw, and two setae (Plate LXIII, fig. 22). 
The second, third and fourth pairs of feet are nearly similar to those of Dactylopodella. 
The fifth pair of feet is somewhat foliaceous. The inner expansion of the proximal joint 
is furnished with three strong inner marginal spines, and two apical spines. The distal joint is 
short and wide. It is furnished with six setae at the distal end (Plate LXIII, fig. 23). 
Male unknown. 
Occurrence. — One specimen was found in the surface plankton collected at Station 
40, off Pulu Kawassang, Paternoster Islands. 
Genus Pseudothalestris Brady, 1883. 
This genus was established by Professor G. S. Brapy in 1883, in the report on 
the ‘Challenger’ Copepoda. It is closely related to the genus Westwoodia Dana, in the 
structure of the appendages, but it differs very considerably in having the exopodite of the 
first pair of feet composed of two distinct joints. The exopodite is only one-jointed in true 
Westwoodia. 
Professor G. O. Sars ‘Crustacea of Norway’ Vol. V, disestablished this genus, owing 
to the fact that he obtained a species (Westwoodia asstmzlis) with the exopodite of the 
first pair of feet composed of two joints, but in all other respects agreeing so closely with 
the type of the genus Westwoodza that a very careful examination was required to separate 
it from Westwoodia nobzis (Baird). This reason appears to be scarcely sufficient for cancelling 
Pseudothalestris especially as it is a common occurrence to find species belonging to different 
genera included under one family that possess some character common to all, yet differing 
in other points. The two-jointed exopodite of the first pair of feet is evidently not accidental, 
and it is surely of as much value in generic distinction as the large fifth pair of feet of 
Phyllothalestris, or the greatly developed rostrum of Rhyuchothalestris, which are regarded 
by Sars of so much importance, that he separates these forms from typical Zhalestris. 
Diva 
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