THE SUGAE-BEET THEIPS, 7 



Protliorax transverse, about three-fourths as wide as long; length 0.158 mm.; 

 width 0.232 mm.; margins rounded; a row of setse extending aroimd the margins, 

 with the exception of the anterior margin. Mesothoracic angles prominent and 

 acute;^width 0.282 mm. Wing pads extend to the middle of the fifth abdominal 

 segment, each forewing pad bearing 12 to 13 short spines; length of wing pad from 

 base to apex 0.564 mm. 



Abdomen fusiform, tapering slightly anteriorly; segments 9 and 10 much narrower 

 than the rest, each bearing a pair of large obtuse spines, which extend upward. Each 

 segment except 1, 9, and 10 bears two dorsal pairs of setae, one placed laterally and 



^^^:iis 



Fig. 5.— Third-stage nymph 

 of sugar-beet thrips. En- 

 larged about 40 diameters. 

 (Original.) 



Fig. 6.— Fourth-stage nymph 

 of sugar-beet thrips. En- 

 larged about 40 diameters.. 

 (Original.) 



one sublaterally. The first segment is without setae, and 9 bears two pairs on lateral 

 margin ; 10 bears only one pair. 



Legs translucent white, bearing numerous short spines, with one long spine on 

 the tibise. 



THE ADULT. 



The adult female (fig. 7) is described by Hinds as follows: , 



Heliothrips femohalis Reuter. 



Female. — Length 1.3 mm. (1.12 to 1.5 mm.); width of mesothorax about one-fourth 

 the body length. General color dark brown to yellowish brown, lighter at extremi- 

 ties. Entire surface of body weakly but plainly reticulated. 



Head two-thirds as long as Ijroad, widest in front; anterior margin depressed at 

 in.sf^nion of antennae; vertex carinated; bases of antennae separated by a prominence 

 as high and nearly as wide as the first antennal segment; two transverse wrinkles near 

 ba<^:k of head more prominent than the others; Ijehind the anterior one of these two 

 the longitudinal parts of the reticulations Ijecome very faint,; sjnnes upon head scat- 

 tering and small. Eyes (juite large, [trotruding anteriorly, coarsely granulated; 

 eyea and margins of ocelli bright, dark red by reflected light; ocelli placed on sides 



