. Copepoda. Calanoida; Copepoda. 6o COPEPODA probably an indication of the final ecdysis. The mouth limbs are scarcely different from those of mature females. The males are always easily distinguished from the females by the presence of the well developed pes V (text-fig. 13 d) which consists of two basal segments and two terminal ones (Re), which especially on the right side, are not always so well distinguished as figured by Canu (PI. II fig. 6). In this stage varieties similar to those of mature females but less marked were found. Y. (Stage IV). Size: o-g—1-4 mm. But for the presence of onl
. Copepoda. Calanoida; Copepoda. 6o COPEPODA probably an indication of the final ecdysis. The mouth limbs are scarcely different from those of mature females. The males are always easily distinguished from the females by the presence of the well developed pes V (text-fig. 13 d) which consists of two basal segments and two terminal ones (Re), which especially on the right side, are not always so well distinguished as figured by Canu (PI. II fig. 6). In this stage varieties similar to those of mature females but less marked were found. Y. (Stage IV). Size: o-g—1-4 mm. But for the presence of only 3 somites in the abdomen this stage is like the preceding one, and shows similar differences between the two sexes (text-figs. 13 e—f). Y. (Stage III). Size: 07 — ro mm. This stage, of which Stephen sen has given figures of all the limbs, shows no sexual differences, and is characterized by four natatory legs and two abdo- minal somites. Y. (Stage II). Size. 0-5—0-8 mm. This stage has three natatory legs and two abdominal somites. The last copepodite stage as well as the larval forms was not with security found out; I refer to Ob erg's description. Variation. From Iceland I have examined a female (taken 25/6 1902 by Ditlevsen in Heste- reyrifjorde) with a spermatophor attached to the genital somite, in which a fairly well developed c fifth pair of legs was observed (cf. text-fig. 14 a—b). The Ingolf Exp. (at St. 49 100—o fm.) has taken a full-grown female? alike the preceding but with much longer pes V, of which the left is longer than the right (text-fig. 14 c). The 0. Exp. 1900 (F. 451) has taken a female with a right and left pes V of almost equal length; the Re III of left pair is rounded and short, without terminal seta; the corresponding segment of the right side is more elongate. From Ingolf (St. 29 V1 50—o fm.) I have examined a young animal ($?) with a rudimentary pair of legs, consisting of two short basal segments, and a rounded small terminal seg
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Keywords: ., bookauthorhansenhj, bookcentury1900, bookdecade1910, bookyear1915
