THE MONTHLY BULLETIN. 



31 



THE GREENHOUSE THRIPS. 



HcUoflniii.s InniKJirhoiddlix Bouche. 

 (Fig. 28.) 



General Appearance. — The adult insect is characterized by having 

 the antennje eight-segmented and twice as long as the head, while the 

 surface of the body is distinctly reticulated. The abdomen is yellowish 

 brown, with head and thorax dark brown and antenna?, legs and wings 

 colorless. 



Fig. 2 8. — The greenhouse tlirips { Ileliothrius hirmorrhoidalis Bouche) ; 

 adult female and antenna. (After Russell.) 



Life History. — The very minute, bean-shaped, colorless eggs are 

 inserted in the leaf tissues cf the food plants, usually on the underside. 

 They hatch in about ten days. Each female lays from ten to twenty 

 eggs. The first hatched larva? are colorless, with seven-segmented an- 

 tennae As they age they become darker in color and the antenna' 

 i)ecome eight-articulated. The larval and pupal stages occupy from 

 four to six weeks. All stages feed throughout their life cycles. There 

 are continuous and overlapping generations, estimated by H. M. Russell 

 to be twelve a year. 



Distribution. — In greenhouses throughout the State. Also abund- 

 ant in the open, especially in the central and southern parts of the State. 



