. Bulletin. Natural history; Natural history. August, 1944 Ross: Caddis Flies of Illinois 243 and not very rigid in construction; a few larger stones are frequently attached at the sides. Adults.—Length 10-12 mm. Color brown with a reddish cast, without distinct mark- ings ; specimens in liquid showing a con-. Fig. 834.—Oecetis inconspicua larva. spicuous dark bar across the cord. Position of crossveins forming the cord extremely variable, ranging from a condition in which the three crossveins form an almost straight line to one in which they are far removed and steplike. Male genitalia, fig.
. Bulletin. Natural history; Natural history. August, 1944 Ross: Caddis Flies of Illinois 243 and not very rigid in construction; a few larger stones are frequently attached at the sides. Adults.—Length 10-12 mm. Color brown with a reddish cast, without distinct mark- ings ; specimens in liquid showing a con-. Fig. 834.—Oecetis inconspicua larva. spicuous dark bar across the cord. Position of crossveins forming the cord extremely variable, ranging from a condition in which the three crossveins form an almost straight line to one in which they are far removed and steplike. Male genitalia, fig. 824: tenth tergite forming a single, straight, fairly long rod; cerci short and ovate; claspers with dorsal margin incised to form a conspicuous ventral lobe, their ventral margin somewhat angulate at base; aedeagus almost circular, with short beak. Female genitalia, fig. 831, with ninth sternite membranous and not bounded by dark lines, the apical shelf straight and bursa copulatrix simple. This species is one of the most common caddis flies in Illinois and has been taken throughout the state. It is one of the few caddis flies abundant in artificial ponds. The larvae live in both lakes and streams. They are seldom encountered in field col- lections but are frequently present, together with those of cinerascens, in fish stomachs. The adults emerge throughout the warmer months, from May until early October, and frequently occur in immense numbers. The species is very widely distributed throughout the North American continent and appears to be fairly rare only in the Northwest. We have records from Ala- bama, Arkansas, British Columbia, Cali- fornia, Cuba, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Massachusetts, Mexico, Michigan, Minne- sota, Missouri, Nebraska, New Brunswick, New Hampshire, New York, Nova Scotia, Ohio, Oklahoma, Ontario, Oregon, Penn- sylvania, Quebec, Saskatchewan, South Carolina, South Dakota, Texas, Utah, Vir- ginia and Wisconsin
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