218 



COPEPODA 



was found in segments 12 and 14, but not in segment 18. The Sp. of segment 24 does not extend to 

 the end of segment 25. The segments 8 — 12 are 1-4 as long as segments 23 — 25, and segment 19 is n 

 as long as 23. The antennae, mandibulae and maxillulae are practically like those of the adult females. 

 The sensory organs of the maxillae are better developed, and the maxillipcds show the usual differences. 

 The natatory legs are scarcely different from those of the females. 



The fifth pair of legs is distinctly longer than the abdomen. The right leg (text-fig. 69 b) has 

 the third basipodite rounded in the usual way ; inwards a short process is found, where the endopodite 

 is articulated; this extends distinctly beyond the end of the first outer segment, is gradually attenuated, 

 distally curved and here slightly hollowed. The first outer segment has several projections medially, 

 and is distinctly produced inwards terminally, where is the outwards convex second segment, with a 

 shallow excavation facing forwards and inwards; the third segment is short and somewhat attenuated 

 (text-fig. 69 c). 



The basipodites of the left leg are, as usual, long and slender; the endopodite, which extends 



somewhat beyond the first outer segment, is a thin, elongated 

 structure with indication of segmentation in the middle, some- 

 what enlarged terminally, and with a small terminal seta. The 

 left exopodite consists of two segments of almost equal length; 

 the second is somewhat enlarged, and is terminated with 2 — 3 

 leaf-like structures in addition to a slender hook-shaped organ 

 dissolved into "setae" terminally, and a plate with at least 7 long 

 serrations (text-fig. 69 d and PI. VIII figs 14 a — b). 



The labrum etc. are in all features of interest like those 

 of the female; a curious feature was, however, found in the 

 arrangement of the hairs on the anterior surface, as the oblique 

 row of hairs between the two convex rows was wanting. 



Text-fig. 70. Scottocalamis Thorn n. sp. 



a. Y9 (St. V). Head X 33- b. Abdomen X 33- 



c. Pes V in post, view X 59- d. YcP (St. V). 



Pes V X 59- 



Y£ (St. V). Size of female from Thor St. 88 was 3-84 mm.; 

 anterior division 3-06 mm; urosome 078 mm. Male from St. 82 measured 3-63 mm. 



The shape of the body (text-figs 70 a — b) is in the main like that of the adult female, but the 

 frontal keel is just indicated; the fifth thoracic somite is well marked in front, and its lateral corner 

 is produced into a short but distinct tooth. The abdomen consists of four somites, of which the second 

 is longer than the first and third, which are of equal length and longer than the fourth. The first 

 abdominal somite has a small process on the left side; the serrated membrane of the somites II — IV 

 is only indicated. The appendages are, with the exception of the fifth pair of legs, like those of the 

 adult females as well as alike in the two sexes. In the female (text-fig. 70 c) the fifth foot consists of 

 three distinct, almost square segments in addition to a short terminal one, produced into a short spine, 

 at the base of which an exterior delicate hair is found; at the base of the last segment a strong 

 spine is found, at least as long as the 3 distal segments. The fifth pair of the male consists of two 

 short basal segments in addition to the undivided branches, somewhat asymmetrical (text-fig. 70 d). 



Occurrence. The Ingolf Expedition has not gathered this species, but it was taken at the 

 following stations by the Thor, 





