. Bulletin - United States National Museum. Science. Figure 211.—Oncaea borealis: a. Female, lateral; 6, female, urosome; c, male, urosome Color.—Body transparent and colorless except for a faint tinge of yellow, which is deepest around the mouth and in the bases of the mouth parts and the swimming legs. Female.—Metasome fusiform, two and one-third times as long as wide; second thoracic segment with a dorsal hump as in the pre- ceding species. Urosome half the length of the metasome; genital segment scarcely longer than the abdomen, and tapered posteriorly; anal segment shorter than the two pr
. Bulletin - United States National Museum. Science. Figure 211.—Oncaea borealis: a. Female, lateral; 6, female, urosome; c, male, urosome Color.—Body transparent and colorless except for a faint tinge of yellow, which is deepest around the mouth and in the bases of the mouth parts and the swimming legs. Female.—Metasome fusiform, two and one-third times as long as wide; second thoracic segment with a dorsal hump as in the pre- ceding species. Urosome half the length of the metasome; genital segment scarcely longer than the abdomen, and tapered posteriorly; anal segment shorter than the two preceding segments combined; caudal rami much shorter than anal segment. Fifth leg rounded oval in form, its apical setae about the same length. Total length, mm. Male.—M u c h smaller and more slender than the female; second tho- racic segment without a dorsal hump; urosome much less than half the length of the metasome; genital segment very large, three times the width and twice the length of the abdomen, lappets at its posterior corners short, bluntly rounded, and extending straight back; maxillipeds larger than those of the female, the apical claw smooth. Total length, mm. Remarks.—Sars's separation of this species from conifera seems perfectly valid, and the two may be recognized by the characters given in the key above. This is more strictly a northern form, as is expressed in its specific name, and it has never been found much nearer the Tropics than in the present area. ONCAEA MINUTA Giesbrecht Figure 212 Oncaea minuta Giesbrecht, Fauna und Flora des Golfes von Neapel, vol. 19, p. 591, pi. 47, 1892. Occwrrence.—Both sexes were obtained in a vertical haul at a depth of 1,000 meters, March, 1920, at Station 20069, Grampm, just south of Georges Bank. Distribution.—North Atlantic (Cleve) ; Mediterranean (Gies- brecht) ; Indian Ocean (Thompson and Scott); Greenland coast (Stephensen); coast of Norway (Sars); coast of California (Es- terly); Ches
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