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Genus Phyllopus Brady, 1883. 
The members of this genus are readily recognised by the structure of the fifth pair of 
feet of the two sexes. The female fifth pair has a two-jointed basiopodite, and a three-jointed 
exopodite. There is no trace of an endopodite on either foot. The terminal joint of the exopodite 
is leaf-like. The apex is rather deeply and irregularly serrate. The male fifth pair is well 
developed and prehensile. The exopodite of each foot is two-jointed. The left foot only is 
furnished with a rudimentary lamelliform endopodite. 
The genus was established by Brapy in 1883 from a single specimen that was undoubtedly 
a female. WOLFENDEN’s statement, in the Journal of the Marine Biological Association, April 
1904, page 124, that it was a male is a curious error as he describes the male in the same 
report. The late I]. C. THompson appears to have been the first observer to give an account 
of the male, but he wrongly identifies his species with the type of the genus. THompson, 
WoLFENDEN and EsrTerty state that the right foot has a rudimentary endopodite. This is an 
error due to an imperfect preparation or a reversal of the right and left sides. Esrerty, however, 
only found one female and his description of the male was taken from WoLFENDEN’s report. 
There appears to be some confusion regarding the type species. Other forms have been 
recorded by some writers as Phyllopus bedentatus that are clearly distinct. FARRAN (1908) has 
done much to clear up the difficulty, and has established two additional species. 
Four species belonging to this genus were obtained from the plankton collected by the 
‘Siboga’ in the Malay Archipelago. 
1. Phyllopus bidentatus Brady. Plate XLV, figs. 1—9. 
Phyllopus bidentatus Brady, 1883, p. 78, pl. V, figs. 7—16. 
Phyllopus bidentatus T. Scott, 1893, p. 74, pl. VI, fig. 26. 
Phyllopus bidentatus Sars, 1905 (0), p. 5. 
Eight males and three females apparently identical with Brapy’s type species were found 
in the plankton collected at the following stations. 
Stat. 118 (HENSEN vertical net, g00 metres to surface), 1 male. — Stat. 128 (HENSEN vertical 
net, 700 metres to surface), 1 male, 1 female. — Stat. 141 (HENSEN vertical net, 1500 
metres to surface), I male, 1 female. — Stat. 185 (HENSEN vertical net, 1536 metres to 
surface), 2 males. — Stat. 203 (HENSEN vertical net, 1500 metres to surface), 1 male. — 
Stat. 216, 1 male. — Stat. 276 (HENSEN vertical net, 750 metres to surface), 1 male and 
1 female. 
The females although resembling Brapy’s type in the prolongation of the last thoracic 
segment, differ from it by the projection being obliquely truncate at the apex, when seen from 
the side, instead of distinctly forked as shewn by that author. The terminations of the last 
thoracic segment are asymmetrical, both in length and in shape. The left side extends to the 
middle of the genital segment. The apex is pointed (Plate XLV, fig. 3). The right side extends 
to near the distal end of the genital segment. The apex is obliquely truncate, with a very 
minute point at each extremity (Plate XLV, fig. 4). 
The combined length of the abdomen and furca is equal to slightly more than one 
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