1. Scaphocalanus magnus (T. Scott). 
Amallophora magna T. Scott, 1893, p. 55, pl. IV, figs. 5—9. 
Scolecithrix cristata Giesbrecht, 1895, p. 252, pls. II & III. 
Scolecithrix cristata Giesbrecht & Schmeil, 1808, p. 48. 
Scaphocalanus acrocephalus Sars, 1900, p. 36, pls. VII, VIII & Ix. 
Amallophora magna Sars, 1902, p. 51, pls. XXXIV & XXXV. 
Scolecithrix cristata I. C. Thompson, 1903, p. 21 (female only). 
Amallophora magna Wolfenden, 1904, p. III. 
Scolecithrix cristata Farran, 1905, p. 36. 
Amallophora magna Sars, 1905(a), p. 6. 
Amallophora magna Pearson, 1906, p. 17. 
Scolecithrizxz magna Esterly, 1906, p. 66, pls. 9, 11, 12, 13. 
Scolecithrix magna Farran, 1908, p. 51. 
Scolecithrix magna van Breemen, 1908, p. 76, fig. 89. 
Males and females of this species were obtained from the plankton collected at the 
following stations. 
Stat. 96 (day), 1 specimen. — Stat. 118 (HENSEN vertical net 900 metres to surface), I spe- 
cimen. — Stat. 138, 1 specimen. — Stat. 141 (HENSEN vertical net 1500 metres to surface), 
2 specimens. — Stat. 143 (HENSEN vertical net 1000 metres to surface), 2 specimens. — 
Stat. 168, 2 specimens. — Stat. 203 (surface), 2 specimens. — Stat. 276 (HENSEN vertical 
net 750 metres to surface), I specimen. 
The females of Scaphocalanus magnus are easily distinguished from the other members 
of the genus, by the presence of a distinct helmet-shaped crest on the forehead. Nine females 
and three males were obtained. 
Leneth. -— Female 4,5—5 mm. Male 4,5 mm. 
Scaphocalanus magnus is apparently widely distributed. It ranges from the tropical Atlantic 
and Pacific, to the North Polar basin. Farran records it from the West of Ireland, and my 
father has obtained it from the Farée Channel. 
2. Scaphocalanus major (T. Scott). 
Scolecithrix major T. Scott, 1893, p. 52, pls. II] & V. 
Scolecithrix major Giesbrecht & Schmeil, 1898, p. 47. 
Scolecithrix major 1. C. Thompson, 1903, p. 20. 
Scolecithrix major van Breemen, 1908, p. 79, fig. 92. 
Five females belonging to this species, were obtained from the plankton collected with 
the HENSEN vertical net at the following stations. 
Stat. 128 (7oo metres to surface), 1 specimen. — Stat. 141 (1500 metres fo surface), I spe- 
cimen. — Stat. 143 (1000 metres to surface), 1 specimen. — Stat. 185 (1536 metres to 
surface), I specimen. — Stat. 243 (1000 metres to surface), I specimen. 
The female of this species has no trace of a median cephalic crest. The last thoracic 
segment when viewed from the side, appears very narrowly rounded, but there is no indication 
of a point, as in Scaphocalanus magnus, or Scaphocalanus elongatus. 
The species was described by my father as a Scolectthrix, but the character of the spines 
on the fifth pair of feet, shew that it is a true member of this genus. 
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