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Stat. 19, 2 specimens. — Stat. 35, 3 specimens. — Stat. 36, 3 specimens. — Stat. 37, 15 
specimens. — Stat. 40. — Stat. 66, 5 specimens. — Stat. 75, 16 specimens. — Stat. 81, 
4 specimens. — Stat. 93, 7 specimens. — Stat. 96 (day). — Stat. 96 (night). — Stat. 98, 
20 specimens. — Stat. 99. — Stat. 106. — Stat. 110, 3 specimens. — Stat. 112, 3 specimens. — 
Stat. 117°. — Stat. 118, 5 specimens. — Stat. 124, 15 specimens. — Stat. 125. — Stat. 128. — 
Stat. 129, 3 specimens. — Stat. 133. — Stat. 136, 75 specimens. — Stat. 138, 90 specimens. — 
Stat. 144. — Stat. 146. — Stat. 148, 8 specimens. — Stat. 149. — Stat. 157. — Stat. 165, 
33 specimens. — Stat. 168, 3 specimens. — Stat. 169, 46 specimens. — Stat. 172. — 
Stat. 177%. — Stat. 184, 65 specimens. — Stat. 185. — Stat. 186, 8 specimens. — Stat. 
189°, IO specimens. — Stat. 193, 8 specimens. — Stat. 203 (surface), 2 specimens. — 
Stat. 203 (1500 metres), 8 specimens. — Stat. 204, 25 specimens. — Stat. 205, 10 specimens. — 
Stat. 210%, 15 specimens. — Stat. 213, 15 specimens. — Stat. 214. — Stat. 2157, 50 
specimens. — Stat. 216. — Stat. 217 (horizontal cylinder), 100 specimens. — Stat. 220 
(vertical net), 8 specimens. — Stat. 220 (surface), 15 specimens. — Stat. 223, 3 specimens. — 
Stat. 224, 7 specimens. — Stat. 225, 5 specimens. — Stat. 229, 10 specimens. — Stat. 
243, IO specimens. — Stat. 245, 5 specimens. — Stat. 276. — Stat. 282, 11 specimens. — 
Stat. 304. 
The peculiar projection of the last thoracic segment, and the row of fine spines at the 
distal end of the abdominal segments, help to identify the females of this species from Undznula 
vulgaris, and the peculiar form of the exopodite of the left fifth foot, renders the identification 
of the males comparatively simple. The endopodite of the male left fifth foot is rudimentary, 
and consists of a single small joint. Some care has to be taken in separating the male of 
Undinula darwin, from that of Undinula carol, as the exopodite of the left fifth foot of the 
two species has a very similar structure. 
3. Undinula carol (Giesbrecht). 
Calanus carol: Giesbrecht, 1888, p. 331. 
Calanus caroli Giesbrecht, 1893, p. 91, pl. 8, fig. 36: 
Calanus caroli Giesbrecht & Schmeil, 1898, p. 17. ’ 
Calanus caroli Wolfenden, 1895 (a), p. 994, pl. XCVII, fig. 41. 
This species although widely distributed throughout the area traversed by the ‘Siboga’ 
appeared to be comparatively rare. The following are the stations where it was noted. 
Stat. 37, 2 specimens. — Stat. 75, 2 specimens. — Stat. 93, 1 specimen. — Stat. 98, 2 
specimens. — Stat. 124. — Stat. 136, 2 specimens. — Stat. 138, 5 specimens. — Stat. 148, 
2 specimens. — Stat. 165, 4 specimens. — Stat. 186, I specimen. — Stat. 210%, 1 specimen. — 
Stat. 217 (horizontal cylinder), 1 specimen. — Stat. 220, I specimen. 
The difficulty in distinguishing this species from Uxdinula darwinz, is no doubt the cause 
of the paucity of records since it was established by Gresprecut. WOLFENDEN is apparently 
doubtful that it is really distinct from Uxdinula darwint. It must be admitted, that considerable 
care is necessary to make out the species when mixed up with Undinula darwinz, but when 
the difference is once seen, further identification is comparatively easy. The position of the tooth 
on the inner edge of the external spine, which is part of the last joint of the exopodite of the 
left fifth foot, is the specific character separating the two species. In Uxdinula carolz, the tooth 
is placed about one-sixth from the base of the spine, and five-sixths from the distal end. The 
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