46 INSECTS INJURIOUS TO STAPLE CROPS. 



as well as by nurserymen and greenhouse florists. The 

 grub becomes full-grown in the summer of the second year 

 after hatching from the egg. 



It then forms a small oval cell from three to ten inches 

 below the surface of the soil, and here changes to the 

 pupa. The pupal stage lasts slightly over three weeks. 

 Late in August or early in September another transforma- 

 tion takes place and the adult beetle wriggles out of the 

 pupal skin, but remains m the earthen cell until the fol- 

 lowing spring, when it comes forth fully hardened in May 

 or June. The beetles at once pair, and the females 

 deposit their eggs and soon die. Thus three full years are 

 consumed in the complete life-cycle of each brood. 



hijiiry. — Having seemingly formed a dislike to the light 

 of day from their long subterranean existence, the adult 

 beetles feed and pair entirely at night. The foliage of 

 almost all of the common forest- and shade- and occa- 

 sionally fruit-trees suifers from their attacks. Injury to 

 maple-trees has been specially observed. About 9 p.m. of 

 an evening early in June, thirty-five beetles were once 

 taken by the writer from a small silver-maple tree about 

 eight feet in height, and they were equally numerous on 

 all of a long row of these trees. 



But the grubs and beetles are too common to need 

 description and may be recognized from the figures. It 

 may not, however, be known that the term ^^ white 

 grubs ^' is generally applied to the larvae of many distinct 

 species of the genus Lachnosterna and one of Cyclocephala, 

 which so far as known have practically the same habits, 

 except that the larvae of the latter genus remain over 

 winter as dormant larv^ and pupate in May. 



By cutting off the tap-root and feeding roots of corn. 



