23° 



COPEPODA 



Y£ (St. V). Size of female from Thor St. 183 was 6-15 mm.; anterior division 4-9 mm.; urosome 

 1-25 mm. 



The shape of the body is more slender than in the adult female. Short, but distinct rostral, 

 filaments were found in the examined specimen. The comparative length of the abdominal somites 

 and the furcal branches is 30, 50, 40, 20 and 17; the somites are distinctly hirsute. The appendages 

 do not show any difference of importance, except the fifth pair of legs; this was in one specimen (St. 

 167) shorter than that of the adult female, and especially the last segment was less slender; in another, 

 however (St. 183) (fig. 17 f PI. VIII), the last segment was, as seen in figure, divided into two; as the 

 right and the left foot were almost quite alike, I am most disposed to regard this feature as an 

 abnormity and not as one characteristic of the male. 



Y$ (St. IV). Size of female from Thor St. 183 was 4-36 mm.; anterior division 3-44 mm.; uro- 

 some 0-92. 



The comparative length of the abdominal somites and the furcal branches is 28, 40, 40 and 17. 

 The maxillulac have only 9 setae in the exopodite. The natatory legs show the usual differences, as 

 the Ri II — III and Re II — III are fused; the second to fourth pairs of legs have only 3 Se in the Re 

 II 00 III. The fifth pair of legs (PI. VII 6 e) is rather short and clumsy, with the first outer seta of 

 Re III rather indistinct. 



Occurrence. The Thor has taken this species in Denmark Strait: 

 '9/ 6 1904 St. 152 65°oo U N. 28°io h. W. 1 f?. 



In the Atlantic, south of Iceland: 



I0 / 7 1904 St. 180 6i°34 L. N. i9°o5 L. W. Yt. 1800 M. Wire 1 y? (V). 



"/ 7 1904 St. 183 6i°30 Iv. N. i7°o8 h. W. Yt. 1800 M. Wire 3 f$, 5 f<?, 2 y? (V), 1 y? (IV). 



2I / 5 1904 St. 99 6i°i5 L. N. 9^5 L. W. Yt. 1500 M. Wire 1 f$. 



In the Iceland-Faeroe channel: 



2 9/ 8 1904 St. 165 6o°oo L. N. io°35 L. W. Yt. 1000 M. Wire iy?. 

 22 / s 1904 St. 99 6i°i5 h. N. 9^5 L. W. Yt. 1700 M. Wire 1 £?; 1 y? (V). 

 4/ 8 1904 St. 230 63°io Iv. N. 7°3i L. W. Yt. 1200 M. Wire 1 f?. 



In the Atlantic, south west of the Faeroes: 



9/ 6 1905 St. 72 57^2 L. N. 9°55 L. W. Yt. 1500 M. Wire 2 f$, 3 y? (V), 2 y? (IV). 



Distribution. This species has previously been recorded from the North-East Atlantic and is, 

 according to Farran, not uncommon off the west coast of Ireland "at depths of from 330 to 1150 

 fathoms"; the other records are rather doubtful. 



Remarks. On full consideration I do not doubt that the females and males are rightly referred 

 to the same species. 



My specimens differ from Wolf en den's original description by its much larger size, and by 

 the maxillae, which do not possess "seven short thick brush processes", and, from a note (1906 p. 32) 

 by the number of setae in the third basipodite and the endopodite of the maxillulae. It differs from 

 Sars' O. trigoniceps by its size and the anteriorly well marked first thoracic tergite. 





