METEOROLOGICAL OBSERVATIONS. 



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Monroe county at Brighton and Mendon, and many more ; in Livingston, 

 Wayne, Onondaga, Ontario and Cayuga counties, in all of which the 

 seventeen year fly appeared in 1814, 1831, 1848, and 1865. The pupse 

 come to the surface of the earth in the last week in May or the first 

 week in June ; and at Mendon, in the last year, had all appeared by 

 the 11th of June. In Ohio, their appearance at Marietta was in 1795 

 and in the following seventeenth year regularly ; in Pennsylvania, in 

 1715, and then in each seventeenth year to 1851; in Sandwich, Mass. 

 in 1787, and every seventeenth year to 1855 ; in Maryland in other 

 series of years ; and in South Carolina and Georgia in still another series. 

 In each locality the appearance is regularly each seventeenth year, 

 though a straggler is sometimes seen in other years. These Harvest 

 Flies probably feed on the mucilage or honey-dew of the leaves, by 

 means of their tube or sucker. They cannot eat the leaves or wood 

 being destitute of mouth and jaws ; and it is not yet ascertained that 

 they do any injiury to vegetation. 



