52 
Stat. 66, I specimen. — Stat. 141, 2 specimens. — Stat. 142, I specimen. — Stat. 203 
(Hensen vertical net), I specimen. — Stat. 245, I specimen. — Stat. 252, 1 specimen. 
One female and six males were found. Female — length 3 mm. Male — length 2,87 mm. 
The species described by my father from the Gulf of Guinea in 1893 as Euchaeta hessez 
var. s¢mtlis, appears to be undoubtedly the male of the form described by Giesbrecht in 1895 
as Gaidius pungens, from females only. Gazdius pungens Giesbrecht, will therefore, necessarily, 
give way to Gazdius similis (T. Scott), The fifth pair of feet of the male figured in the 
‘Report on Entomostraca from the Gulf of Guinea’, only differs from that shewn in the present 
report, by the absence of the endopodite of the left foot. This no doubt, is due to the fact 
that the endopodite lies close to the exopodite, and may easily become folded under it. I find 
too, that the exopodite of the first pair of feet in some of the males may be very indistinctly 
three-jointed, according to the state of maturity. 
I regard the form described by Sars as Gazdius (Chiridius) tenuispinus, that has been 
recorded by Farran, PEARSON, and vAN BREEMEN, from the North Atlantic, to be identical with 
this species. . 
The first joint of the exopodite of the right foot of the males from the ‘Siboga’ material, 
has a lamella-like process on the middle of the inner margin, which may be very easily overlooked. 
The species apparently has a wide distribution. 
2. Gaidius notacanthus Sars. Plate XXI, figs. 24—33. 
Gaidius notacanthus Sars, 1905(a), p. 9. 
Gaidius notacanthus Farran, 1908, p. 33, pl. III, fig. 7. 
One specimen, a male, apparently belonging to this species was found in plankton 
collected with the HENsEN vertical net at Station 148, 1000 metres to surface. Length 5,9 mm. 
The fifth pair of feet agrees fairly well with the figure given by Farran, except that 
the second joint of the right exopodite is shorter, but this may be due to accident or slight 
immaturity. 
The records by Sars and Farran appear to be all that is known of the distribution of 
this species. 
Genus Gaidiopsis nov. 
Forehead without cephalic spine, with short one-pointed rostrum. The fourth and fifth 
thoracic segments are completely separated, and the fifth segment is produced into strong lateral 
spines. The abdomen is composed of four joints. The antennules are twenty-four-jointed. The 
antennae, mandibles, maxillae and maxillipedes, are almost similar to those of Gazdius. The 
exopodite of the first pair of feet is distinctly three-jointed. The second, third and fourth pairs 
of feet are similar to those of Gazdzus. The endopodite of the second pair is distinctly two-jointed. 
This new genus resembles -#2zdcopszs, in the complete segmentation of the fourth and 
fifth thoracic segments, and the distinctly three-jointed exopodite of the first pair of feet. It also 
resembles Gazdzus in the short one-pointed rostrum. 
Only one species was observed and the male is unknown. 
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