. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE SUGAE-BEET THKIPS. 5 about on the leaf with the abdomen curved downward, but if dis- turbed moves rapidly away with short, quick leaps. It seldom takes wing, although the wi'iter has twice observed flight for a short dis- tance. A beet leaf showing the adult at rest is illustrated in Plate II. The adult males are smaller and more active than the females, which usually greatly outnumber them, although at times the pro- portion becomes nearly equal. Copulation takes place during the day, as has been observed on a num
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. THE SUGAE-BEET THKIPS. 5 about on the leaf with the abdomen curved downward, but if dis- turbed moves rapidly away with short, quick leaps. It seldom takes wing, although the wi'iter has twice observed flight for a short dis- tance. A beet leaf showing the adult at rest is illustrated in Plate II. The adult males are smaller and more active than the females, which usually greatly outnumber them, although at times the pro- portion becomes nearly equal. Copulation takes place during the day, as has been observed on a number of occasions. Oviposition usually takes place at night or in the evening, but has been observed late in the afternoon. DESCRIPTIVE. THE EGG. Egg (fig. 2) translucent white; surface without sculpture; elongate reniform, slightly- flattened at cephalic end. Average length mm.; width mm. Deposited usually on the underside, obliquely to the surface, and beneath the epidermis of the leaf or stem. TMien the embryo begins to develop, the egg becomes swollen and tmns dull white. THE NYMPH. First stage (fig. 3).—Fusiform, translucent white; head, eyes, Fig 1 \ , . 1 \. 1 1 1 thrips. Enlarged. legs, and prothorax large in proportion to the rest of the body; (Original) length mm. Head sub quadrate; slightly rounded in front. Length mm.; width at eyes mm The eyes dark red, ocelli absent. Antennae, length mm.; the seg- ments confused with the exception of 2 and 3, which are separate; segments 1 and 2 cylindrical, bearing spines on outer margins; segment 2 slightly longer; segment 3 pedunculate, annulate, bearing spine on outer anterior margin; segment 4 fusi- form, annulate, nearly twice as long as 3, bearing two spines on upper margin; seg- ments 5, 6, 7, and 8 slender and tapering toward apex; spine on outer margin of segment 5. The head bears two pairs of setae dorsally, and one in front of the eye on the outer margin. Prothor
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