. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. COPEPODA 8i Remarks. In spite of the small differences enumerated in the description, I do not doubt that this species is identical with that described by Sars from Norwa}', and with that which Wolfenden has described under the name of Psaidaetiditis from the Faeroe channel. According to my investigations the size of the specimens varied from 3-6 to 4-4 mm., the biggest being those from northern regions; Farran's (1905) specimens measured 3-3â3'5 mm., aud even 265; these small specimens possibly belong to another species. 17


. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. COPEPODA 8i Remarks. In spite of the small differences enumerated in the description, I do not doubt that this species is identical with that described by Sars from Norwa}', and with that which Wolfenden has described under the name of Psaidaetiditis from the Faeroe channel. According to my investigations the size of the specimens varied from 3-6 to 4-4 mm., the biggest being those from northern regions; Farran's (1905) specimens measured 3-3â3'5 mm., aud even 265; these small specimens possibly belong to another species. 17. Chiridius nasutus n. sp. (PI. II fig. 4a; text-figs i8aâe). 1905. pars? Chiridius armatus Boeck. Farran. Description. f$. Size: Specimen from St. 167 2-88 mm.; anterior division 2-19 mm.; urosome 0-69. The shape of the body is in the main like that of the preceding species, but somewhat more slender (text-fig. 18 a). The insertion of the antennulae is apparently better removed from the tip and the rostral spines, which are somewhat longer '' 'â and basally swollen, and directed more forwards (text-figs 18 bâc). The anterior division is just three times as long as the abdomen. The genital somite (text-fig. 18 d), which has a receptaculum seminis like that of Ch. arviatus, is about 1-5 as long as the third and 17 as long as the fourth somite; the furcal rami are 17 as long as wide and 17 as long as the anal somite; the last segment is about half as long as the third one. The antennulae, which extend some- what beyond the end of cephalothorax, but scarcely to the end of the abdominal somite, have the segments 24 and 25 well defined; the measurements differ only n ' a e in minor details, as the segment 20 is a little longer Text-fig. 18. Ch. nasutus n. sp. ^,0 ^, i o â 1 â , (^l,â.- a. Head in dorsal view X 16. b. Rostrum from below X 150- than 8000 as the segment 18 is a little longer than â , ⢠w i ⢠v, < a o»â; .^.^u,. »+. v sr. "' '^ c. H


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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1915