66 
Euchaeta concinna, although not very common, appeared to be well distributed throughout 
the area investigated by the ‘Siboga’ as shewn by the following records. 
Stat. 16. — Stat. 19. — Stat. 35. — Stat. 36. — Stat. 37. — Stat. 40. — Stat. 66. — 
Se oe Sam to =o Sais O& = See ues, —= Sink mio, — Sia, nig, — Sek aaa, 
Stat. 125 (day). — Stat. 128. — Stat. 136. — Stat. 138. — Stat. 141. — Stat. 143. — 
Stat. 144. — Stat. 146. — Stat.1448. — Stat. 157. — Stat. 165. — Stat. 168. — Stat. 
169. — Stat. 172. — Stat. 177°. — Stat. 184. — Stat. 185. — Stat. 186. — Stat. 189. — 
Stat. 220 (vertical net). — Stat. 230. — Stat. 243. — Stat. 245. —. Stat. 252. — Stat. 
282. — Stat. 315. 
The female of this species is easily recognised, by the peculiar projection on the proximal 
end of the right side of the genital segment. The armature on the margin of the second joint 
of the left exopodite of the male fifth pair is finer than in Auchaeta marina. The outer-edge spine 
on the second joint of the exopodite of the second pair of feet of the female, is moderately long 
and stout. It extends nearly to the apex of the first spine on the third joint. The outer-edge 
spines on the third joint are very short. 
Fiuchaeta concinna appears to be confined to the tropical seas. 
3. Euchaeta longicornis Giesbrecht. 
Euchaeta 
FEuchaeta 
Euchaeta 
Euchaeta 
Euchaeta 
One female 
HENSEN vertical net 
This species 
identification. When 
beyond the furca. 
longicornis Giesbrecht, 1888, p. 337. 
longicornis Giesbrecht, 1893, p. 246, pls. 16 & 37. 
longicornis Giesbrecht & Schmeil, 1898, p. 40. 
longicornis Cleve, I9OI, p. 7. 
longicornis Cleve, 1904, p- 190. 
belonging to this species was found in the plankton collected with the 
at Station 141, 1500 metres to surface. 
is closely related to Euchaeta marina, and some care is required in its 
the antennules are perfect these form a very good character as they extend 
4. Euchaeta media Giesbrecht. Plate XX, figs. 10—18. 
Luchaeta 
Euchaeta 
Euchaeta 
Euchaeta 
Euchaeta 
One female 
HENSEN vertical net 
media Giesbrecht, 1888, p. 337. 
media Giesbrecht, 1893, p. 246, pls. 16 & 37. 
media Giesbrecht & Schmeil, 1898, p. 39. 
media Cleve, 1904, p. 190. 
media Esterly, 1905, p. 160, fig. 25. 
belonging to this species was found in the plankton collected with the 
at Station 230, 2000 metres to surface. 
Euchaeta media resembles LFuchaeta acuta very closely, but it can be distinguished by 
the following characters. The left side of the genital segment, when viewed from above, is seen 
to be considerably swollen. It is broadly rounded in outline, but is not produced into a pointed 
process. The posterior margin of the last thoracic segment appears distinctly angular, when 
seen from above, and from the side. The outer-edge spine on the second joint of the exopodite 
66 
