. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. Text-figure 8. Megacalanus princeps Wolfenden. a. Head of adult female X 16. b. Abdomen of adult female > d. .\bdomen of young female (stage V). 15. c. Pes I in situ X 67. 16. Description f$. Size: 10-5 mm. (anterior division 8-5; urosome 2). The head is slightly produced between the base of the antennulae and is without any crest. The rostral filaments are short and placed on a low elevation just above the rostrum, composed of a short basal part and two slightly convergent rather obtuse, fairly long spines, directed back
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. Text-figure 8. Megacalanus princeps Wolfenden. a. Head of adult female X 16. b. Abdomen of adult female > d. .\bdomen of young female (stage V). 15. c. Pes I in situ X 67. 16. Description f$. Size: 10-5 mm. (anterior division 8-5; urosome 2). The head is slightly produced between the base of the antennulae and is without any crest. The rostral filaments are short and placed on a low elevation just above the rostrum, composed of a short basal part and two slightly convergent rather obtuse, fairly long spines, directed backwards and downwards. The five thoracic somites are well distinguished; the fifth is laterally triangularly produced. Projecting from the hinder margin of the head a small process, similar to that of Macrocalanus, though less prominent, is observed. The abdomen is only one fourth of the anterior division in length. The genital somite is as long as deep and wide, and in front ventrally produced. The antennulae^ which are at least 8 segments longer than the body, have all 25 segments well separated, except the VIII and IX, with the articular membranes wanting posteriorly. The segments increase in length from the 8 to the 17; beyond the 19 they are much shorter; the 23 is 1-4 as long as the 25, which is only i-i as long as the penultimate one. The 13 and 14 have in the distal part, ventrally and exteriorly, a row of delicate teeth (according to Wolfenden they are found in seg- ment 12 and 13). The bristles of the antennulae are rather delicate; the posterior setae of segment 23—24 are rather weak, and scarcely 1-5 as long as two distal segments (in Scott's figure they are Tlie Ingolf-Expcdition. III. 4. 6. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ingolf (Cruiser); Danish Ingolf-Expedition (1895-1896). C
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1915
