ORDER VIII. THYSANOPTERA. 



THRIPID.^. 



This order contains the family Thripidse, represented 

 by Thrips striatus (Fig. 62 ; hair-line represents 

 natural size), an insect too small for sat- 

 isfactory class-work. This species feeds 

 upon onion plants, while Thrips cerealium 

 is the little black insect which destroys 

 large quantities of wheat. Specimens of 

 other species can be obtained from daisies 

 and clover. The mouth parts of Thrips are 

 interesting organs, since they are interme- 

 diate in form between the true sucking and 

 biting mouth parts. The mandibles are 

 bristle-like, but both pairs of maxillae, with 

 palpi, are developed. The feet are very curious, ending 

 in bulbs ; on this account these insects are often called 

 Physopoda. The remarkable fringed wings possessed 

 by Thrips have given the name Thysanoptera {Ovaa- 

 vo?, fringe ; Trrepov, wing) to the order. These are 

 not without their parallels, and similar modifications 

 occur in some minute Lepidoptera (Pterophoridae) 

 and Hymenoptera (Proctotrupidae). These appear to 

 us to be cases of similar specializations in the same 

 parts. 



The species of Thrips have larvae which are remark- 



Fig. 62. 



