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Calocalanus pavo Wolfenden, 1905(a), p. 999. 
Calocalanus pavo Pearson, 1906, p. 9. 
Calocalanus pavo van Breemen, 1908, p. 22, fig. 18. 
Calocalanus pavo although not common, had a moderately wide distribution throughout 
the area traversed by the ‘Siboga’ as shewn by the records given. 
Stas UO, —= Stet, AQ, <= Seti, 27, — Sia. GO, — Sie 75, —= Siete OO (Gey, — Sie, 06 
(night). — Stat. 99. — Stat. 1o1. — Stat. 110. — Stat. 118. — Stat. 121. — Stat. 133. — 
Stat. 138. — Stat. 141. — Stat. 148. — Stat. 203 (1500 metres to surface). — Stat. 213. — 
Stat. 215°. — Stat. 217 (horizontal cylinder). — Stat. 220 (vertical net). — Stat. 224. — 
Stat. 229. — Stat. 243. — Stat. 271. — Stat. 276. — Stat. 282. — Stat. 304. 
This species is easily identified by its two-jointed abdomen, and by the peculiar position 
of the furcal joints. The furcal joints are symmetrical and are nearly always spread at right 
angles to the abdomen. None of the specimens had the caudal setae in the perfect condition 
so well shewn by GIEsBRECHT. 
Calocalanus pavo has a wide distribution in the warm seas, and it has been frequently 
recorded from various parts of the great oceans. 
2. Calocalanus plumulosus (Claus). 
Calanus plumulosus Claus, 1863, p. 174, pl. XXVI, figs. 15 & 16. 
Calocalanus plumulosus Giesbrecht, 1893, p. 176, pls. 3, 9, 36. 
Calocalanus plumulosus T. Scott, 1893, p. 39, pls. 1 & 6. 
Calocalanus plumulosus Giesbrecht & Schmeil, 1898, p. 26. 
Calocalanus plumulosus Wheeler, 1900, p. 170, fig. 8. 
Calocalanus plumulosus A. Scott, 1902, p. 403. 
Calocalenus plumulosus Thompson & Scott, 1903, p. 243. 
Calocalanus plumulosus Wolfenden, 1905 (a), p. 999. 
This Calocalanus appeared to be rather a rare species in the area investigated, and 
was only observed in the plankton collected at the following eleven stations. 
Staessen tate State7.54 —— eStats) 121s Stat 4O™ —— Stats 048.) Stat. 14. 
Stat. 217 (horizontal cylinder). — Stat. 271. — Stat. 282. — Stat. 304. 
Calocalanus plumulosus is easily separated from Cadocalanus pavo, by its three-jointed 
abdomen and asymmetrical furca. The left furcal joint is larger than the right, and it is not 
separated from the anal segment. The left furcal joint is furnished with a very long plumose 
seta, but this is seldom perfect in specimens taken in ordinary tow-net collections. 
This species has a distribution somewhat similar to the previous one. 
4. Family PSsEUDOCALANIDAE. 
Genus Clausocalanus Giesbrecht, 1588. 
This genus is distinguished from the other members of the family chiefly by the structure 
of the fifth pair of feet of both sexes. The fifth pair is symmetrical in the female and has 
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