GRAMINEOUS CROPS. 



Ill 



ratus to a very serious extent. . . . The moth is 

 about three-fourths of an inch in the spread of the fore 

 wings, which are of pale grey with darker transverse 

 markings; the hinder wings are remarkable for their 

 whitish semi-transparency, with a darker line from the 

 point along a part of the fore edge. The larvae, when 

 full grown, are about five-eighths of an inch long, of a 

 palish flesh-colour, lighter when older, and heads of a 

 yellowish-brown colour." i 



Fig. 43. — The Hessiah Fly {Cecidomyia destructor). 



A. and B. The fly (nat. size and enlarged). 



C. Papa-cases of the fly (nat. size). 



D. Pupae in joint of stem. 



Prevention and Cure. — ^Miss Ormerod writes that she 

 " has much reduced their (the larvae) numbers by getting 

 the manager of the steam-mill to turn on scalding steam ; 

 and cleaning, white-washing, and some use of paraffin 

 have done good. The real cure would be to change the 

 material ground. If we could use rye-meal for a few 

 weeks, we could clean out this wheat-flour feeding cater- 

 pillar effectually." 



The Hessian Fly (Cecidomyia destructor, Fig. 43) 



' Miss Ormerod, in Eiley's Insect Life, vol. i. p. 315. 



