194 



larvae of C.fusciceps, while undecayed heads were more or less infested 

 with C. brassicae. These facts suggested that C.fusciceps is a secondary 

 cabbage pest, attacking plants only after decay has set in, possibly as 

 the result of injury by C. brassicae. Certain observers, however, 

 believe that C. fusciceps is a primary pest of growing crops ; Fletcher 

 states that maize sown during a cold, wet period is very liable to be 

 injured. In the discussion which followed, other evidence was given 

 of the primary importance of the insect. In Michigan and in Canada 

 this fly is very injurious to young bean plants. In south Idaho, in 

 1914, large areas of beans were completely destroyed, while potatoes 

 following a wheat crop of the previous year were seriously damaged. 

 In Wisconsin it was found hibernating in the pupal stage in onions 

 and was bred from both cabbage and onion. In Kansas, serious cases 

 of infestation were recorded on maize which followed wheat. 



ScHOENE (W. J.). Notes on the Biology of Pegormjia brassicae, Bouch§. 

 Jl.Econ. Entom., Concord, ix, no. 1, February 1916, pp. 136-139. 



The spring brood of adults of Chortophila {Pegomyia) brassicae, Bch., 

 which emerges from over-wintering pupae, appears first in western 

 New York between 1st and 16th May. Emergence continues for 

 about five weeks. The date of the first appearance may be influenced 

 by the character of the soil, depth of ploughing and slope of the land. 

 Adults maturing in the summer emerge very irregularly, on account 

 of the varying retardation of the developmental stages by conditions, 

 of temperature. Experiments showed that between 56° F. and 78° F. 

 there was practically no delay in the transformation of the pupae ; 

 when a high temperature was maintained, a few completed development 

 in a few days less than the average period, while the rest remained 

 quiescent. When these retarded individuals were kept at a low 

 temperature, only a few emerged, and many died. A similar 

 retardation of the development of the larvae and pupae of the 

 Hessian fly [Mayetiola destructor] is caused by high temperature 

 or severe drought. The number of broods which occur annually is 

 directly connected with delay in development. In western New York 

 there were three effective broods in 1909, while in 1911 only one brood 

 was of any importance. 



Dean (G. A.). The Hessian Fly Train. — Jl. Econ. Entom., Concord, 

 ix, no. 1, February 1916, pp. 139-141, 1 plate. 



This paper describes the special arrangements made by the Kansas. 

 Agricultural College for the purpose of delivering lectures on the habits, 

 etc., of the Hessian fly [Mayetiola destructor] throughout the infested 

 regions of Kansas. 



GossARD (H. A.). County Cooperation to reduce Hessian Fly Injury. 



■ — Jl. Econ. Entom., Concord, ix, no. 1, February 1916^ 

 pp. 142-145. 



During the autumn of 1915 efforts were made in Miami County, 

 Ohio, to secure the cooperation of farmers in fixing a date for the 

 sowing of wheat, in order to reduce as far as possible the injury by the 

 Hessian fly [Mayetiola destructor]. This was effected by inviting the 



