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2. Augaptilus filigerus (Claus). 
Hemicalanus filigerus Claus, 1863, p. 179. 
Augaptilus filigerus Giesbrecht, 1893, p. 400, pls. 3, 27, 28, 29 & 39. 
Augaptilus filigerus Giesbrecht & Schmeil, 1898, p. 121. 
Augaptilus filigerus 1. C. Thompson, 1903, p. 28. 
Augaptilus filuger Sars, 1905(8), p. 4. 
Augaptilus filigerus Farran, 1908, p. 77. 
Augaptilus filigerus van Breemen, 1809, p. 133, fig. 150. 
One specimen belonging to this species was found in the plankton collected with the 
HENSEN vertical net at each of the following stations. 
Stat. 118 (900 metres to surface). — Stat. 141 (1500 metres to surface). — Stat. 143 (1000 
metres to surface). — Stat. 148 (1000 metres to surface). — Stat. 276 (750 metres to surface). 
Augaptilus filigerus can be separated from the other members of the genus, by the 
proportional length of the abdominal segments and furcal joints. The second and third segments 
of the abdomen are of about equal length. The furcal joints are slightly longer than broad. 
They are as long as the anal segment. 
This species was originally obtained from the Mediterranean by Ctaus. It has since 
been recorded from the North Atlantic. 
3. Augaptilus hecticus Giesbrecht. 
Augaptilus hecticus Giesbrecht, 1889, p. 814. 
Augaptilus hecticus Giesbrecht, 1893, p. 400, pls, I, 27, 28, 29 & 39. 
Augaptilus hecticus Giesbrecht & Schmeil, 1898, p. 122. 
Augaptilus hecticus 1. C. Thompson, 1903, p. 29. 
Augaptilus hecticus van Breemen, 1908, p. 135, fig. 153. 
One specimen of this Augapte/is was found in the plankton collected with the HENsEN 
vertical net at each of the two following stations. 
Stat. 141 (1500 metres to surface). — Stat. 276 (750 metres to surface). 
This species is a comparatively small one. It can be distinguished by the proportional 
length of the abdominal segments and furcal joints. The second and third segments of the 
abdomen are of about equal length. The furcal joints are as long as the anal segment. They 
are three times longer than broad. 
Augaptilus hecticus has a moderately wide distribution. It has been recorded from the 
Atlantic and Pacific Oceans and from the Mediterranean. 
4. Augaptilus longicaudatus (Claus). 
Flemicalanus longicaudatus Claus, 1863, p. 179, pl. XXIX. 
Augaptilus longicaudatus Giesbrecht, 1893, p. 400, pls. 27, 28, 29 & 309. 
Augaptilus longicaudatus T. Scott, 1893, p. 34, pls. I & II. 
Augaptilus longicaudatus Giesbrecht & Schmeil, 1898, p. 123. 
Augaptilus longicaudatus 1. C. Thompson, 1903, p. 29. 
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