new 
Stat. 66, I specimen. — Stat. 141 (HENSEN vertical net, 1500 metres to surface), 2 speci- 
mens. — Stat. 143 (HENSEN vertical net, 1000 metres to surface), 1 specimen. — Stat. 
148 (HENSEN vertical net, 1000 metres to surface), I specimen. — Stat. 185 (HENSEN 
vertical net, 1536 metres to surface), 2 specimens. — Stat. 203 (HENSEN vertical net, 1500 
metres’ to surface), 2 specimens. — Stat. 217 (horizontal cylinder), 1 specimen. — Stat. 
220 (HENSEN vertical net, 200 metres to surface), 1 specimen. — Stat. 243 (HENSEN vertical 
net, 1000 metres to surface), 2 specimens. — Stat. 276 (HENSEN vertical net, 750 metres 
to surface), 1 specimen. — Stat. 304, 1 specimen. — Stat. 315, 1 specimen. 
Heterorhabdus spinifrons can readily be ‘separated from the other members of the genus 
by the rostral papilla ending in sharp points, and by the strong curved spine on the upper 
surface of the first basal joint of the second pair of maxillipedes. 
This species has apparently a moderately wide distribution in the great oceans. 
3. fHeterorhabdus longicornis (Giesbrecht). 
Fleterochaeta longicornts Giesbrecht, 1889, p. $12. 
Fleterochaeta longicornis Giesbrecht, 1893, p. 373, pls. 20 & 30. 
Heterorhabdus longicornis Giesbrecht & Schineil, 1898, p. 116. 
Heterorhabdus longicornis 1. C. Thompson, 1903, p. 27. 
Heterorhabdus longicornis Wolfenden, 1904, p. 112. 
Heterorhabdus longicornts Sars, 1905 (6), p. 3. 
Fleterorhabdus longicornis Farran, 1905, p. 45. 
Fleterorhabdus longicornis Esterly, 1905, p. 186, fig. 4o. 
FHleterorhabdus longicornis Pearson, 1906, p. 26. 
Heterorhabdus longicornis Esterly, 1906, p. 77. 
Fleterorhabdus longicornis Farran, 1908, 67. 
Heterorhabdus longicornis van Breemen, 1908, p. 125, fig. 144. 
Eight females and three males belonging to this species were found in the plankton 
collected at the following stations. 
‘Stat. 128 (HENSEN vertical net, 700 metres to surface), I specimen, — Stat. 141 HENSEN 
vertical net, 1500 metres to surface), 2 specimens. — Stat. 143 (HENSEN vertical net, 1000 
metres to surface), 2 specimens. — Stat. 148 (HENSEN vertical net, 1000 metres to surface), 
2 specimens. — Stat. 203 (HENSEN vertical net, 1500 metres to surface), I specimen. — 
Stat. 243 (HENSEN vertical net, 1000 metres to surface), 2 specimens. — Stat. 276 (HENSEN 
vertical net, 750 metres to surface), I specimen. 
This species is readily distinguished from the other members of the genus by its very 
long antennules. The antennules extend beyond the end of the furca by eight or nine joints. 
The distribution appears to be very similar to that of Heterorhabdus spinifrons. 
4. Heterorhabdus papilliger (Claus). 
Heterochaeta papilligera Claus, 1863, p. 182, pl. XXXII. 
Fleterochaeta papilligera Giesbrecht, 1893, p. 372, pls. 20 & 39. 
Heterorhabdus papilliger Giesbrecht & Schmeil, 1898, p. 114. 
FHererochaeta papilligera Cleve, 1901, p. 7. 
Heterorhabdus papilliger 1. C. Thompson, 1903, p. 27. 
Heterorhabdus papilliger Thompson & Scott, 1903, p. 249. 
131 
