. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 38 COPEPODA. from the 8 to the 17 segments, but decrease from the 20 to the 24, which is scarcely half as long as the 23, which is of almost equal length to the 25. In the basal segment ouly 2 terminal setae are observed; the second segment bears three tritheks, and the following 17 segments bear a single one, consisting of rather delicate setae; the 20—23 segments have only 2 terminal setae (Sd + "^sthe- taskeu"), the 24 segment has a single long and slender seta and the 25 segment has 6. Segment 22 has a delicate
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 38 COPEPODA. from the 8 to the 17 segments, but decrease from the 20 to the 24, which is scarcely half as long as the 23, which is of almost equal length to the 25. In the basal segment ouly 2 terminal setae are observed; the second segment bears three tritheks, and the following 17 segments bear a single one, consisting of rather delicate setae; the 20—23 segments have only 2 terminal setae (Sd + "^sthe- taskeu"), the 24 segment has a single long and slender seta and the 25 segment has 6. Segment 22 has a delicate posterior seta (Sp.) and the two last segments each bear a powerful, ringed plumous one, at least twice as long as the two segments combined. Antennae are in the main alike Calamis, but the Si of the Basipodite II is very short and the Re I and II have no Si, but the latter segment has two processes medially. Mandibulae: The manducatory part is rather short with the first to the fifth serrations well developed without accessory teeth; the sixth to the eighth serrations are only poorly developed. The four partly plumous setae, of about equal length, are shorter than the width of the segment. The Ri I has ouly 2 setae and the Ri II has 8 setae anteriorly and a single one posteriorly. Maxillulae: The Le I has the 2 first setae extremely short, almost rudimentary, and the following 7 long and plumous; the Le II is only indistinct without any seta. The Li II, which does not bear any seta, is comparatively shorter than Li III, which is fairly slender with 2 setae only. The Basp. II has 2 moderately slender setae (); the Ri I—II which are indistinctly separated from each other as well as from the basipodite, have a single seta each, while the well distinguished Ri III bears 4 long and one single rather short seta. Re, which has the usual eleven plumous setae, extends a little beyond the end of the endopodite. Maxillae are in most respects alike Calaiitis, but the Lob. V bears
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1915
