. Fresh-water biology. Freshwater biology. 864 FRESH-WATER BIOLOGY seg. IV 4 is also usually modified in the male by the possession of a peg-like projection and characteristic hairs. The species vary considerably in size, from about mm. to nearly 2 mm. One of the most abimdant and widely distributed genera, common in clear, shallow, hard waters where plant life is abundant, with about 200 species, all of various shades of bluish or brownish green, or red. There are about 50 species described from North America. 22 (19) Pal. seg. s not opposable to 4, and bearing at the distal end small mo
. Fresh-water biology. Freshwater biology. 864 FRESH-WATER BIOLOGY seg. IV 4 is also usually modified in the male by the possession of a peg-like projection and characteristic hairs. The species vary considerably in size, from about mm. to nearly 2 mm. One of the most abimdant and widely distributed genera, common in clear, shallow, hard waters where plant life is abundant, with about 200 species, all of various shades of bluish or brownish green, or red. There are about 50 species described from North America. 22 (19) Pal. seg. s not opposable to 4, and bearing at the distal end small more or less distinct teeth or claws 23 23 (44) Epimera in both male and female united and more or less fused into a single epimeral plate .... 24 24 (39) Body more or less compressed dorso-ventrally and completely en- closed in a chitinous covering usually divided into a smaller, elMptical or oval, dorsal plate and a larger ventral plate. Subfamily Aturinae. 25 25 (26) Four smaller plates, variously shaped, anteriorly, between the dorsal and ventral Torrenticola Piersig 1897. A rather small mite, to mm. long, of oval form, with the capitulum produced into a sort of snout; no swimming-hairs. One American species, rarely found, and apparently identical with the European Torrenti- cola anomda (Koch). Fig. 1332. Torrenticola anomala (Koch). Ventral surface, female. X 27. Outer side, right palpus, female. X no. (Modified from Piersig.). 26(25) The two plates, dorsal and ventral, covering the whole surface . 27 27 (30) Rostrum developed, prolonged and curved upward 28 28 (29) Genital area without flaps or valves, with numerous acetabula free in the body surface ... Tanaognathus Wolcott 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 Ward, Henry Baldwin, 1865-1945; Whipple, George Chandler, 1866-1924
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
