278 K. STEPHENSEN. 
x 43. Pseudalibrotus Nanseni G. O. Sars? 
Pseudalibrotus Nanseni G. O. Sars, Crust.; Nansen, The Norweg. North 
Polar Exped. 1893—96, Sci. Results, vol. 1, 
Nr. 5, 1900, р. 26, Pl. 4—5. 
Bredefjord Sermilik St. 118, 500 m. w., 5 spec.; St. 119, 400 
m. w., 1 spec. — Bredefjord St. 126, 800 m. w., 2 spec. 
The material from these stations includes some specimens of an 
Amphipod belonging to the genus Pseudalibrotus. With the large 2. 
joint of p7 they resemble P. Nanseni, but differ in various points. Hardly 
any of them are full grown, save possibly that from St. 119. 
I am inclined to think that the specimens in question must be 
young individuals of P. Nanseni, the resemblance being so great that 
the differences may presumably be taken as due to the fact that the 
specimens were not fully grown. A more serious objection, however, 
is the locality. Sars’ original specimens were taken “about 80° latitude, 
north of the New Siberian Islands. The specimens seem not to have 
been taken by the aid of the tow-net, but on bait hung down from the 
ship. Moreover, some young specimens ... occured in a sample much 
farther west, near the 85th degree of latitude”; these were thus from a 
distinctly arctic locality. My specimens, on the other hand, were taken 
pelagically, under boreal conditions. Although this fact need not in 
itself be of very great importance, it would hardly support the sugge- 
stion of their belonging to the same species as that described by Sars; 
in the absence of further material, however, I think we cannot do better 
than record the specimens in question as Pseudalibrotus Nanseni? 
For clearness’ sake I have here considered the specimens from 
each station separately, numbering the 5 from St. 118 as from 1 to 5. 
Station 118, specimen Nr. 1 (Fig. 19), 3, length 14mm. Being in 
doubt as to the determination, I have here drawn all appendages, after 
dissection, and will now point out what I consider the most important 
characters; I am, however, inclined to consider the deviation from Sars’ 
description as due to difference in size. (My specimen is 14 mm.; Sars’ 
largest — the one shown in his figure? — 20 mm.). 
On the whole, the resemblance is very good, and I now mention 
differences only. Lateral lobes on the cephalon somewhat more pointed 
that shown by Sars; as to how far the eyes are “contracted above” 
(Sars) I am unable to state with certainty, as they have now lost all 
colour, and are therefore difficult to draw with accuracy; the ocelli at 
the edge are particularly indistinct. The postero-lateral corner of the 
3. epimeral plate in the metasome is more pointed than shown by Sars, 
the point itself especially being more sharply defined. 
In ant. 1, the accessory flagellum has 4 joints (Sars: 4—5), the 
flagellum has 45 (Sars: amounting to about 50 in all), it is furnished 
with setae, though I have not been able to discover calceoli, possibly 
