CHAPTER IV 



THRIPS, BUGS, APHIDES, AND SCALE 

 INSECTS 



minute creatures termed " thrips " make up 

 JL the eighth order, or Thysanoptera, of British 

 insects. They are also called " flower insects," 

 because they abound in blossoms of many kinds, 

 including those of wheat and other cereals. Their 

 mouth-parts are intermediate between the biting and 

 sucking type, some being modified to act as piercers, 

 while in conjunction they form a kind of short pro- 

 boscis, which, when not in use, lies in a cavity beneath 

 the thorax. The most remarkable peculiarity of the 

 mouth-parts, however, is that some of them are 

 asymmetrical i.e., they differ on the two sides. When 

 present, the wings are exceedingly narrow, with long 

 hairs on one or both margins ; but many species are 

 wingless throughout life. The tarsi have one or two 

 joints, and are provided with a bladder-like sucker 

 between the claws. Compound eyes are always 

 present, while in the winged species there are usually 

 three ocelli also. The antennae have from six to nine 

 joints, and are never very long. 



The young thrips closely resemble their parents in 

 form, and have similar habits. The wings are de- 

 veloped outside the body, and are said to become 

 visible after the third moult ; but although the meta- 



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