HEMIPTERA. 167 



vegetable matter, come more quickly to their growth than cater- 

 pillars and other insects which devour living plants ; the former 

 are appointed to remove an offensive nuisance, and do their work 

 quickly ; the latter have a longer time assigned to them, cor- 

 responding in some degree to the progress or continuance of vege- 

 tation. The facilities afforded for obtaining food influence the 

 duration of life ; hence those grubs that live in the solid trunks of 

 perennial trees, which they are obliged to perforate in order to 

 obtain nourishment, are longer lived than those that devour the 

 tender parts of leaves and fruits, which, though they last only for 

 a season, require no laborious efforts to be prepared for food. 

 The harvest-flies continue only a few weeks after their final trans- 

 formation, and their only nourishment consists of vegetable juices, 

 which they obtain by piercing the bark and leaves of plants with 

 their beaks ; and during this period they lay their eggs, and then 

 perish. They are, however, amply compensated for the short- 

 ness of their life in the winged state by the length of their pre- 

 vious existence, during which they are wingless and grub-like in 

 form, and live under ground, where they obtain their food only by 

 much labor in perforating the soil among the roots of plants, the 

 juices of which they imbibe by suction. To meet the difficulties 

 of their situation and the precarious supply of their food, for 

 which they have to grope in the dark in their subterranean re- 

 treats, a remarkable longevity is assigned to them ; and one spe- 

 cies has obtained the name of Cicada septendecim, on account of 

 its life being protracted to the period of seventeen years. 



This insect has been observed in the southeastern parts of 

 Massachusetts, but does not seem to have extended to other parts 

 of the State. The earliest account that we have of it is con- 

 tained in Morton's " Memorial," wherein it is stated that "there 

 was a numerous company of flies, which were like for bigness 

 unto wasps or bumblebees," which appeared in Plymouth in the 

 Spring of 1633. " They came out of little holes in the ground, 

 and did eat up the green things, and made such a constant yelling 

 noise as made the woods ring of them, and ready to deafen the 

 hearers." Judge Davis, in the Appendix to his edition of Sec- 

 retary Morton's "Memorial," states that these insects appeared 

 in Plymouth, Sandwich, and Falmouth in the year 1S04 ; but, if 



