WHEAT FLIES 261 



on the outside of the ear; but as impatient of bright 

 hght, sheltering themselves (roni the sun's rays 

 among the husks. 



Our English naturalists were for many years of 

 opinion, tiiat the insect called the Hessian-fly, so 

 destructive to wheat crops in America, belong< d to 

 the same family {JMuscida:) with the common house- 

 fly; and Mr ^larkwick, an intelligent naturalist, by 

 a series of observations on a British fly {Clilorops 

 pvmilionis, JMeigln) which attacks the stems of 

 wheat, created no little alarm among agriculturists. 

 Markwick's fly is less than a tourth of an inch in 

 length, with dark shoulders striped with two yellow 

 lines, and the maggot is white. He planted roots of 

 wheat containing larvfe in a small flower pot, and 

 covered them with gauze. Each stem produced one 

 of the above flies. The crop of wheat attacked by 

 this maggot, though at lirst it appeared to fail, 

 turned out well in consequence oi numerous side 

 shoots. It is only the early wheat sown in October 

 that is afiected by it.* 



a. The Hessian fly (Cccidomyln d^sl>iirtnr); 6, Markwick fly 

 (l hlorops pumilionu) m.ignilied. 



It now appears that INIarkwick was altoget her 

 mistaken in idcntif\ iiig his insect with the Hessian 

 fly {Ccciilowijia chslniclor, S\v\ which has been 

 accurately described by iMr Say in the ' Journal of 

 the Academy of Natural Sciences of Philadelphia' 



* Mag. Nat. Hist. July 1829, p. 292. 



