. Crustacea. Part H [microform] : Cladocera. Canadian Arctic Expedition (1913-1918); Canadian Arctic Expedition (1913-1918); Crustacea; Cladocera; Cladocères; Crustacés. Fig. l.—Daphnia Icngispina vnr. hyalina forma urrlica nov. forma. Big Lake, Hornartl harbour, Northwest Territories, September 30, 1915. Length, exclusive of spine, mm. The egg-bearing females obtained in September range in length from 0-9 mm. to 1-0 mm., exclusive of the spine, while the February specimens vary from 0-7 mm. to a little more than 0-8 mm. The spine is from a half to two- thirds as long as the body. No ephi
. Crustacea. Part H [microform] : Cladocera. Canadian Arctic Expedition (1913-1918); Canadian Arctic Expedition (1913-1918); Crustacea; Cladocera; Cladocères; Crustacés. Fig. l.—Daphnia Icngispina vnr. hyalina forma urrlica nov. forma. Big Lake, Hornartl harbour, Northwest Territories, September 30, 1915. Length, exclusive of spine, mm. The egg-bearing females obtained in September range in length from 0-9 mm. to 1-0 mm., exclusive of the spine, while the February specimens vary from 0-7 mm. to a little more than 0-8 mm. The spine is from a half to two- thirds as long as the body. No ephippial females were noted in any of the catches from this lake, but six of tlie samples contained parthenogenetic females; the majority of the lattt^r carried only two eggs while a few bore as many as three, and others only one. Wesenberg-Lund also found that the parthenogenetic females of Daphnia longiapina belonging to the microcephala- galeata group, in plankton material from Thingvallavatn lake, Iceland, carried but two or three Flo. 2.—Daphnia longispina var, hitaUna forma aretira. Big Lake, Bernard liarbour. Northwest Territories, February 12, 1916. Length, exclusive of spine, mm. Egg-bearing females were noted in catches obtained from the lake at Bernard harbour on the following dates:— 1. September 30, Ice eight inches, depth of water 19 feet. Many. 2. November 28, 1915. Ice about two feet. Temperature of water at surface 32° F., below surface 32-5°. Few. 3. February 12, 1916. Ice 5 o feet, depth of water 20 feet. Temperature of water at surface 32° F., air 20°. 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 Juday, Chancey, 1871-1944; Canadian Arctic Expedition (1913-1918). Ottawa : T. Mulvey
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectcrustacea, bookyear19
