. Journal of agricultural research . g usually the greater or less drawing up of the under part of the head in with length, breadth, and height about equal; dorsum subshining to shining,with minute dark hairs usually arranged in rows lengthwise. One pair of minute dorso-central bristles before the scutellum, far apart; one supra-alar, two or three notopleural,one humeral, all small. Scutellum of ordinary form, neither flattened nor shining black, without bristles. Halteres yellow. Abdomen black, subshining, rarely the first segment yellowish; the black colorexte
. Journal of agricultural research . g usually the greater or less drawing up of the under part of the head in with length, breadth, and height about equal; dorsum subshining to shining,with minute dark hairs usually arranged in rows lengthwise. One pair of minute dorso-central bristles before the scutellum, far apart; one supra-alar, two or three notopleural,one humeral, all small. Scutellum of ordinary form, neither flattened nor shining black, without bristles. Halteres yellow. Abdomen black, subshining, rarely the first segment yellowish; the black colorextending underneath to the soft part, which is usually paler. Male genitalia oftenprotrude, showing a pair of distinct claspers curved backward, but these may beretracted and invisible. Abdomen of female pointed, ending in a minute pair ofpalpus-like organs, at tip of the telescopic, 3-jointed ovipositor when the latter isextended (fig. 6), but ordinarily so retracted as to be barely visible. Feb. European Frit Fly in North America 457. Fig. 6.—Oscinis frit: Female abdomen, distended ?with eggs and ovi-positor protruded. (From alcoholic specimen, highly magnified.) Legs of ordinary structure; coxae and femora black, the trochanters and knees oftenyellowish; tibiae rarely entirely black, usually paler at base and tip, the fore andmiddle tibiae often wholly yellow, hind ones, however, always with at least a blackring. Tarsi yellow, darkened toward tips. Wings subhyaline, sometimes a little brownish, varying moderately in width; costaextending to fourth vein; the costal segment between the tips of the first and secondveins about i}^ times aslong as the following one;fourth vein ending veryslightly behind the apex;anal angle well developed. MALE GENITALIA Since these organs inmany insects throw agreat deal of light onthe limits of species,the genitalia of about25 males were mounted for study after being boiled for from 5 to 10minutes in 10 per cent caustic potash; among these were 5
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectagricul, bookyear1913
