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Disseta grandis Esterly, 1906, p. 72, pls. 9, 11, 13 & 14. 
Disseta palumbot Farran, 1908, p. 67. 
Heterorhabdus grandis van Breemen, 1908, p. 126, fig. 145. 
Four females and four males apparently identical with GirsBRECHT’s species were found 
in the plankton collected with the Hensen vertical net at the following stations. 
Stat. 141 (1500 metres to surface), 3 specimens. — Stat. 230 (2000 metres to surface), 4 spe- 
cimens. — Stat. 243 (1000 metres to surface), 2 specimens. 
Length — female 8 mm., male 7,75 mm. 
With the exception of the difference in size I see nothing to separate the ‘Siboga’ 
females from the description and figures given by GIESBRECHT. 
The male was unknown when the original description was given but it has been found 
within recent years by Wo.reNpeN in the plankton collected by the ‘Gauss’ and by EstTErty 
in the Pacific. WoLFENDEN described the female and male as Heterorhabdus grandis. ESTERLY 
recognised the identity of his specimens with the genus Dzsse¢a, and named the form Dsseta grandis. 
With the exception of an apparent difference in the proportional length of the abdominal 
segments of the female, and an asymmetrical genital segment, the specimens from the Pacific 
are identical with those obtained by the ‘Siboga’. The abdominal segments of the Copepoda 
are apt to become telescoped at death, and an unnatural shortening may, therefore, easily take 
place, which will give rise to incorrect proportional lengths. The asymmetry of the genital 
segment of EsTERLy’s specimens may be due to accident. The genital segment of the ‘Siboga’ 
females is quite symmetrical as shewn in the illustration. 
The last abdominal segments, and the furcal joints of the male, are similar to those 
of the female. EsTerty’s figure of the male left fifth foot, shews the apical spine on the third 
joint of the exopodite to be short and stout, but the more slender distal portion may easily 
have been damaged. WotrenpeEn’s figure of the fifth pair of the male of Weterorhabdus grandis 
is identical with the one given in this report. 
Difference in size unless accompanied by some other decided feature is of little or no 
specific value. 
Disseta palumbot appears to have a fairly wide distribution. 
2. Disseta scopularts (Brady). Plate XLII, figs. 1—9. 
Leuckartia scopularis Brady, 1883, p. 51, pl. XIV, figs. 1—5. 
Leuckartia scopularis Giesbrecht & Schmeil, 1898, p. 125. 
A single male specimen, evidently identical with Brapy’s Leuckartia scopularis, was 
found in the plankton collected with the HENsEN vertical net at Station 230, 2000 metres to 
the surface. 
The specimen was rather mutilated. The antennules, antennae, mandible palps and 
second maxillipedes were incomplete. The more important characters, however, were intact. 
The biting edge of the mandible (Plate XLII, fig. 4) clearly shews that this Calanoid is not, 
as stated by WoLFENDEN in ‘Plankton Studies’ part I, page 23, a Aeterorhabdus. The biting 
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