2*48 



Corycaeus flaccus Thompson & Scott, 1903, p. 285. 

 Corycaeus flaccus Geve, 1903, p. 361. 



Fourteen specimens of the above species were obtained from the plankton collected 

 with the Hensen vertical net at the followino- three stations. 



Stat. 128 (700 metres to surface), 6 specimens. — Stat. 203 (1500 metres to surface), 3 spe- 

 cimens. — Stat. 276 (750 metres to surface), 5 specimens. 



Corycaeus flaccus resembles Corycacus alatus in general appearance. The abdomen is 

 composed of two segments. The genital segment is considerably inflated and the distal end 

 of the dorsal surface is produced in the middle line into a short blunt tooth-like process. The 

 furcal joints are moderately long and slender, and are about two and a half times longer 

 than the anal segment. The proximal end of the joints is swollen. 



This species has been recorded from the Atlantic, Indian and Pacific Oceans, and from 

 the Mediterranean. 



7. Corycaeus furcifcr Claus. 



Corycaeus furcifer Claus, 1863, p. 157, pi. XXIV, figs. 7 — 12. 

 Corycaeus furcifcr Giesbrecht, 1893, p. 660, pis. 49 & 51. 

 Corycaeus furcifer I. C. Thompson, 1900, p. 291. 

 Corycaeus furcifer Cleve, 1901, p. 6. 

 Corycaeus furcifer A. Scott, 1902, p. 421. 

 Corycaeus furcifer Thompson & Scott, 1903, p. 285. 

 Corycaeus furcifer Cleve, 1904, p. 188. 



This species appeared to be moderately frequent and fairly well distributed in the area 

 investigated by the 'Siboga'. It was found in the plankton collected at the following stations. 



Stat. 50. — Stat. 98. -- Stat. 118 (HENSEN vertical net, 900 metres to surface). — Stat. 128 

 (HENSEN vertical net, 700 metres to surface). — Stat. 129. — Stat. 133. — Stat. 141 (HENSEN 

 vertical net, 1500 metres to surface). — Stat. 144. • ■ Stat. 157. — Stat. 165. — Stats. 

 194 — 7. — Stat. 203 (HENSEN vertical net, 1500 metres to surface). — Stat. 214. — Stat. 

 217. — Stat. 217 (horizontal cylinder). — Stat. 220 (HENSEN vertical net, 200 metres to 

 surface). -- Stat. 223. — Stat. 224. — Stat. 225. — Stat. 276 (HENSEN vertical net, 750 

 metres to surface). — Stat. 282. 



The abdomen of the female of Corycaeus furcifer is composed of two segments. The 

 furcal joints are long and slender, and are nearly twice as long as the abdomen. 



This Corycaeus has been recorded from the Atlantic, Indian and Pacific Oceans, and 

 from the Mediterranean. 



8. Corycaeus gibbulus Giesbrecht. 



Corycaeus gibbulus Giesbrecht, 1891, p. 481. 

 Corycaeus gibbulus Giesbrecht, 1893, p. 660, pi. 51, 

 Corycaeus gibbulus I. C. Thompson, 1900, p. 293. 

 Corycaeus gibbulus Cleve, 1901, p. 6. 

 Corycaeus gibbulus A. Scott, 1902, p. 420. 

 Corycaeus gibbulus Thompson & Scott, 1903, p. 286. 

 Corycaeus gibbulus Cleve, 1903, p. 361. 

 Corycaeus gibbulus VVolfenden, 1905(1-?), p. 1028. 



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