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i. Scaphocalanus magnus (T. Scott). 



Amallophora magna T. Scott, 1893, p. 55, pi. IV, figs. 5 — 9. 



Scolecithrix cristata Giesbrecht, 1895, p. 252, pis. II & III. 



Scolecithrix cristata Giesbrecht & Schmeil, 1898, p. 48. 



Scaphocalanus acrocephalus Sars, 1900, p. 36, pis. VII, VIII & IX. 



Amallophora magna Sars, 1902, p. 51, pis. XXXIV & XXXV. 



Scolecithrix cristata I. C. Thompson, 1903, p. 21 (female only). 



Amallophora magna Wolfenden, 1904, p. 111. 



Scolecithrix cristata Farran, 1905, p. 36. 



Amallophora magna Sars, 1905 (a), p. 6. 



Amallophora magna Pearson, 1906, p. 17. 



Scolecithrix magna Esterly, 1906, p. 66, pis. 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 collectecl at the 

 following stations. 



Stat. 96 (day), 1 specimen. — Stat. 118 (HENSEN vertical net 900 metres to surface), 1 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), 1 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. * 



Length. — 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 Faröe Channel. 



2. ScapJiocalanus major (T. Scott). 



Scolecithrix major T. Scott, 1893, p. 52, pis. III & V. 

 Scolecithrix major Giesbrecht & Schmeil, 1898, p. 47. 

 Scolecithrix major I. 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 (700 metres to surface), 1 specimen. — Stat. 141 (1500 metres to surface), 1 spe- 

 cimen. — Stat. 143 (1000 metres to surface), 1 specimen. — Stat. 185 (1536 metres to 

 surface), 1 specimen. — Stat. 243 (1000 metres to surface), 1 specimen. 



The female of this species has no tracé 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 ScolecilJirix, 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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SIROGA-EXPEDITIE XXIX a. 



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