186 INDIRECT INJURIES CAUSED BY INSECTS. 



in Suffolk, is often very much injured, as is also the par- 

 snip, by a small centipede (Geophilus electricus), and an- 

 other polypod (Polydesmus complanatus), which eat into 

 various labyrinths the upper part of their roots; and 

 they are both sometimes totally destroyed by the maggot 

 of some dipterous insect, probably one of the Muscidtz. 

 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. Revett 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 direc- 

 tion, 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. The Death's -head-hawk-moth 

 (Acherontia Atropos) in its larva state feeds upon its 

 leaves, though without much injury. In America it is 

 said to suffer much from two beetles (Cantharis cinerea 

 and vittata), 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 potato, and thus occasioned such a failure of this ex- 

 cellent esculent, especially in one parish, that a collec- 

 a Illiger, Mag. i. 256. 



