. Bulletin of the Department of Agriculture. Agriculture. THE CITEUS THRIPS. 15. in color. The antenna? are directed forward and are 4-jointed. The eyes, at first almost colorless, finally show a red pigmentation in about two-thirds of the facets. The wing pads, which are almost colorless, transparent saclike projections, the hind pair pro- jecting slightly farther than the fore pair, extend to or slightly beyond the hind margin of the second abdominal segment at the beginning of this in- star and reach to the hind margin of the third segment before transformation to the second-instar pup
. Bulletin of the Department of Agriculture. Agriculture. THE CITEUS THRIPS. 15. in color. The antenna? are directed forward and are 4-jointed. The eyes, at first almost colorless, finally show a red pigmentation in about two-thirds of the facets. The wing pads, which are almost colorless, transparent saclike projections, the hind pair pro- jecting slightly farther than the fore pair, extend to or slightly beyond the hind margin of the second abdominal segment at the beginning of this in- star and reach to the hind margin of the third segment before transformation to the second-instar pupa. The second-instar pupa.—The second-instar pupa (fig. 7) is at first but slightly larger than the advanced propupa. The color is pale, translucent yellowish. The antennae are apparently 4-jointed, but the exact number of joints is confused by the ringed appearance due to transitional tissues seen through the pupal sheath. They are directed backward over the head and prothorax, extending to a point near the middle of the latter. All facets of the eyes are red pigmented. The ocelli are visible and translucent. The wing pads at first extend to the hind margin of the sixth abdominal segment or slightly beyond, but project as far as the ninth or tenth segment just before the molt to the adult. Long weak spines are moderately conspicuous on antennas, legs, and hind angles of the ab- dominal segments. There is less growth in the pupal stage than in the larval stage. The average length soon after the molt to the propupa is mm. (about inch); shortly before the first pupal molt it is mm. Just before the last molt it averages to mm. (about inch). The wing pads increase on an average about mm. in length during the first in- star, and show a gain after molting to the second instar of to mm. After the molt to the adult stage the wings exceed the tip of the abdomen. Fig. 6.—First-instar pupa of the citrus thrips Highly magnified. (Orig- inal
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
