THE 



BRITISH NATURALIST. 



NEW SERIES, 



THE HESSIAN FLY IN SOUTH DEVON. 



BY FRED. V. THEOBALD, M.A., F.E.S., 



LECTURER IN ECONOMIC ENTOMOLOGY TO THE SOUTH-EASTERN COLLEGE 



OF AGRICULTURE, WYE, KENT. 



During last summer the Hessian Fly, the Cecidomyia destructor of 

 Say, did a considerable amount of damage in South Devon to wheat and 

 barley crops. Few insects can boast of so much careful and widespread 

 investigation as the one in question. Over one hundred articles and 

 pamphlets have been devoted to this fly. It may, therefore, seem 

 unnecessary to swell the number of writings ; such is not the case, how- 

 ever, for in our country little is known of this cereal pest by the 

 agricultural population. Many of the accounts are purely scientific, 

 and by far the greater number hail from our cousins across the 

 Atlantic. Prior to 1886 little seems to have been known in England of 

 this insect. Walker in his work on British Diptera published in 1851, 

 does not mention it, nor do Banks, Westwood, or other economic 

 entomologists, except Curtis, who briefly refers to it in his " Farm 



EXPLANATION OF PLATE IX. 



Fig. 1. — Barley stem, showing Hessian Fly attack ; stem " elbowed down." 



Fig. 2. — Plant of young wheat, showing position of Hessian Fly maggot at a. 



Fig. 3. — Showing " flax seeds," or puparia. 



Fig, 4. — The Hessian Fly — Cecidomyia destructor— magnified. 



Fig. 5. — Natural size. 



( From Miss Orwerod's Report.) 



