. Bulletin. Natural history; Natural history. \[;iv, 1968 Stannard: Till- TiiKii's 11 I INOIS 315 segment IV brown except pale at base, segment V yellow except brown at apex, segments VI-VIII dark brown. Ocellar pigment red. Head flat anteriorly, not protruding in front of eyes. Pedicel of antennal segment III with sharp angulations in profile. Posterior setal comb on abdominal tergite VIII incomplete. Male (macropterous).—Length distended about mm. General color pale yellow, antennae colored as in fe- male but sometimes lighter. Similar to female in general structure. Abdomi- nal sternite
. Bulletin. Natural history; Natural history. \[;iv, 1968 Stannard: Till- TiiKii's 11 I INOIS 315 segment IV brown except pale at base, segment V yellow except brown at apex, segments VI-VIII dark brown. Ocellar pigment red. Head flat anteriorly, not protruding in front of eyes. Pedicel of antennal segment III with sharp angulations in profile. Posterior setal comb on abdominal tergite VIII incomplete. Male (macropterous).—Length distended about mm. General color pale yellow, antennae colored as in fe- male but sometimes lighter. Similar to female in general structure. Abdomi- nal sternites III-VII each with a transverse elliptical glandular area, these areas pale and often difficult to see. Abdominal tergite IX with medi- an setae shortened but not thornlike, lateral setae moderately long. FranklinieUa tritici is the common eastern flower thrips. Its biological equivalent is the western flower thrips, F. occidentalis, which is naturally found west of the Rocky Mountains, rarely by accidental importation in greenhouses in eastern states. Both cause considerable and similar dam- age to many kinds of flowers and newly formed small fruits. The species tritici may be distinguished from others in Illinois by the angular thickenings on the pedicel of antennal segment III. In the Midwest tritici has two color phases, dark and light, with all degrees of coloration in between. The light phase is statewide in distribution in Illinois whereas dark specimens occur mostly in the northern counties. The darker phase, formerly called vari- corne, does not appear in populations to the south or east of Illinois and In- diana; rather such specimens are found to the north in Wisconsin and Canada and to the west in Iowa, Nebraska, and the Dakotas. Our Illinois records of the dark phase are from Andres, Atlas, suburbs of Chicago, Elgin, and St. Anne. No overwintering specimens of tri- tici have ever been found out-of-doors in Illinois. Possibly this species mi- grates north every s
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Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectnaturalhistory
