. Bulletin - United States National Museum. Science. 520 BULLETIN" 15 8, UNITED STATES NATIONAL MUSEUM. Distribution.—Kattegat, Greenland (Kr0yer); Belgian coast (Beneden); English seas (T. and A. Scott); Skager Rak (Olsson) ; Massachusetts coast (Rathbun). Color.—Body of preserved specimens a uniform brownish yellow. Female.—Head and neck as long as the trunk and of the same diameter throughout; carapace squarely truncated anteriorly. Trunk three times as long as wide; a single pair of posterior processes, small, conical, and ventral to the ovisacs. First antennae with enlarged bases and
. Bulletin - United States National Museum. Science. 520 BULLETIN" 15 8, UNITED STATES NATIONAL MUSEUM. Distribution.—Kattegat, Greenland (Kr0yer); Belgian coast (Beneden); English seas (T. and A. Scott); Skager Rak (Olsson) ; Massachusetts coast (Rathbun). Color.—Body of preserved specimens a uniform brownish yellow. Female.—Head and neck as long as the trunk and of the same diameter throughout; carapace squarely truncated anteriorly. Trunk three times as long as wide; a single pair of posterior processes, small, conical, and ventral to the ovisacs. First antennae with enlarged bases and an apical tuft of setae; second antennae turned across the frontal margin, the endopod 1-seg- mented, with small spines at the tip, the exopod 2-seg- mented and tipped with three spines; second maxil- lae cylindrical and tapered distally; apical claw of maxillipeds with two spines on its inner margin. Length of cephalothorax, 5-6 mm.; of trunk, mm. Male.—Anterior end of head squarely truncated, turned at right angles to the trunk axis and project- ing ventrally beyond the level of the trunk, the antennae and mouth parts arranged along the truncated end. The trunk twice as long as wide, the caudal rami short, conical, and pointed. Both rami of second antennae reduced to mere knobs; palp of first maxilla with a single seta; second maxil- lae no longer than the maxillipeds. Total length, 2 mm. Remarks.—This parasite in the present area is found only on the gills of the halibut and can be recognized by its exceptionally large size. Genus BRACHIELLA Cuvier, 1830 Female.—Cephalothorax elongate and cylindrical, usually flexed; head enlarged and covered by a carapace. Trunk swollen, depressed, and in the larger species with two rows of pit,s or grooves on the dorsal and ventral surfaces; one or two pairs of posterior processes and an unpaired genital process; no abdomen or caudal rami. First antennae 2- to 4-segmented; second antennae biramose, the exopod 2-segmented
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Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
