. Copepoda. Calanoida; Copepoda. The rostrum is strong and directed downwards. The head is, in contrast to Farran's fig. 4, well separated from the first thoracic tergite. The fifth somite is well developed and bears a short, downwards directed hooked spine (text-fig. 42). The abdomen differs from that of the preceding species by being less hairy. The antennulae extend to the end of the chephalosome; the mouth appendages are scarcely different from those of Ch. notacantha. In the structure of the natatory legs scarcely any difference was observed between this and the preceding species. The thi
. Copepoda. Calanoida; Copepoda. The rostrum is strong and directed downwards. The head is, in contrast to Farran's fig. 4, well separated from the first thoracic tergite. The fifth somite is well developed and bears a short, downwards directed hooked spine (text-fig. 42). The abdomen differs from that of the preceding species by being less hairy. The antennulae extend to the end of the chephalosome; the mouth appendages are scarcely different from those of Ch. notacantha. In the structure of the natatory legs scarcely any difference was observed between this and the preceding species. The third foot is shown in text-fig. 42 e. The only difference between male and female is found in the presence of a fifth pair of legs in the former sex; this pair of legs (text-fig. 42 g) is in most respects like that of the preceding species, but differs by the equal length of the two exopodites as well as in a few minor points. In the structure of the labrum and its surroundings no difference of great interest was observed between this species and the preceding ones (cf. PI. VI figs 1 a—b). Y^ (St. IV). Size of male from Thor St. 183 was 3-46 mm.; anterior division 2-8i mm.; uro- some 0-65 mm. The body is more slender, and so is the rostrum; the lateral corners are somewhat more robust (text-fig. 43 f). The abdomen consists of three seg- ments as shown in text-fig. 43 f. The mouth appendages show the usual differences. The exopodite of the first pair of legs shows no trace of segmentation, but has three well developed Se. The endopodite of the second pair of legs is unsegmented, and the two last segments of the exopodite are fused, bearing 3 Se and a single glandular pore at the base of Se 3. The inner margin of the second basipodite of the fourth pair of legs is smooth. The only difference between the male and female is found in the fifth pair of legs, which, as shown in text-fig. 43 h, is less developed than in the preceding stage. f c?. Size of male from Thor St. 183 was 5-28
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Keywords: ., bookauthorhansenhj, bookcentury1900, bookdecade1910, bookyear1915
