INDIRECT INJURIES CAUSED BY INSECTS. 185 



and they are both sometimes totally destroyed by the 

 maggot of some dipterous insect, probably a Musca. I 

 had an opportunity of noticing this in the month of July, 

 in the year 1812, in the garden of our valued friend the 

 Rev. Ilevett Sheppard of OfFton in Suffolk. The plants 

 appeared many of them in a dying state; and upon 

 drawing them out of the ground to ascertain the cause, 

 these larvae were found with their head and half of their 

 body immersed in the root in an oblique direction, and 

 in many instances they had eaten off the end of it. 



America has made us no present more extensively be- 

 neficial, compared with which the mines of Potosi are 

 worthless, than the potato. This invaluable root, which 

 is now so universally cultivated, is often, in this country, 

 considerably injured by the two insects first mentioned 

 as attacking the carrot. In America it is said to suffer 

 much from two beetles {Lytta cinerea and vittata, F.), 

 of the same genus with the blister-beetle a ; and in the 

 island of Barbadoes some hemipterous insect, supposed 

 to be a Tettigonia, occasionally attacks them. In 1734? 

 and 1735 vast swarms of them devoured almost every 

 vegetable production of that island, particularly the po- 

 tato, and thus occasioned such a failure of this excellent 

 esculent, especially in one parish, that a collection was 

 made throughout the island for the relief of the poor, 

 whose principal food it forms. 



The chief dependance of our farmers for the suste- 

 nance of their cattle in the winter is another most useful 

 root, the turnip. And they have often to lament the di- 

 stress occasioned by a failure in this crop, of which these 

 minor animals are the cause, On its first coming up, as 

 a Illfger,>/0g. i. £56. 



