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I do not think the first joint of the basiopodite of the fourth pair of feet would possess the 
armature described by Canu. The three-jointed exopodite of the first pair of feet in Gaetanus 
caudant, is the only noteworthy difference between that species, and the form now dealt with. 
The three-jointed exopodite might easily be changed, and the rudimentary fifth pair of feet be 
suppressed at the final ecdysis. 
I regard Farran’s Gaetanus pileatus to be identical with. Canu’s Gaetanus caudant. 
FARRAN'S type specimen was obtained from the stomach of a mackerel, and even a very short 
exposure to the gastric juices would bring about some changes in the appearance of the 
copepod. The only difference between Farran’s figures and those now given, appears to be in 
the setting of the cephalic spine, and this is probably due to the cause mentioned. Some weight 
is given to the view that Gaetanus pileatus is the same as Gaetanus caudani by the fact that 
Oothrix bidentata Farran (1905), is identical with MVeoscolecethrix koehlert Canu (1896), and 
both these copepods have been taken in some quantity, in the plankton collected from the 
deep water of the Farde Channel, by the Scottish International Fisheries Cruiser ‘Goldseeker’. 
I have compared the Faroe Channel form of long spined Gaetanus with Gaetanus caudani of 
this report, and can find no difference between them. 
ESTERLY’s Gaetanus unicorns is, | think, clearly identical with Gaetanus caudani Canu. 
Gaetanus caudani has apparently a wide distribution, extending from the deep water of 
the Malay Archipelago to the Farde Channel. 
4. Gaetanus minor Farran. Plate IX, figs. 1—8. 
Gaetanus minor Farran, 1905, p. 34, pl. V, figs. 1—11. 
Gaetanus minor Pearson, 1906, p. 14. 
Gaetanus minor Farran, 1908, p. 37. 
Gaetanus minor van Breemen, 1908, p. 41, fig. 46. 
This Gaetanus was obtained from plankton collected with the HENsEN vertical net at 
the following two stations. 
Stat. 141 (1500 metres to surface). — Stat. 276. (750 metres to surface). 
Gaelanus minor is not unlike a small form of Gaetanus armiger, and without careful 
examination, may be easily overlooked. 
The antennules reach to the middle of the abdomen. The cephalic spine is somewhat 
similar to that of Gaefanus armiger, but it is distinctly longer and more conspicuous when 
viewed from the dorsal surface. The spines of the last thoracic segment extend nearly to the 
end of the genital segment. The combined length of the abdomen and furca, is contained about 
three and a half times in the total length of the cephalothorax, from the apex of the cephalic 
spine to the base of the genital segment. The genital segment slightly exceeds the combined 
length of the second and third segments. The rostrum is small and does not appear to be 
divided at the apex. The lamella on the basal joint of the second maxillipedes is bluntly rounded 
at the apex and slightly excavated. The exopodite of the first pair of feet is two-jointed, with 
no trace of a division across the first joint. The first joint of the basiopodite of the fourth pair 
of feet, is furnished with a very few bristles on its inner margin. 
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