ON THE HOUSE-FLY INVESTIGATIONS. 481 



20. Fly Investigations Reports. lY. — Some Enquiry into 

 the Question of Baits and Poisons for Flies, being a 

 Report on the Experimental Work carried out during 

 1915 for the Zoological Society of London. By Olive 

 0. Lodge *. 



[Received March 29, 1916 : Preliminary report read bj' Prof. H. Maxwell Leeuot, 

 November 9, 1915.] 



Index. Page 



Baits for Blow-flies 481 



Baits for House-flies 491 



Poisons for Flies 496 



General Summary 515 



l^iote on JEmpusa muse cB 515 



Note ou Proportion of Sexes in House-flies 515 



List of Abbreviations 516 



Tliese experiments testing various substances on flies, were 

 made with the object of finding out which were the most suitable 

 to use as baits for traps, while others were tested as possible 

 poisons. The work was undertaken under the direction of 

 Prof. H. Maxwell Lefroy for the Zoological Society of London, 

 during the summer and autumn of 1915. 



The experiments in connection with Blow-flies were made in 

 the Society's Gardens, Regent's Park ; those on House-flies, at 

 Acton Lodge, Brentford ; while the work on poisons was done, 

 for the most part, at the Imperial College of Science and Tech- 

 nology, South Kensington. 



Baits for Blow-flies. 



The well-known habits of blow-flies, and their attraction to 

 dead and decaying animal matter, suggested three main lines of 

 enquiry for experiment on blow- fly baits : — 



I. To try to find out whether any of the decomposition pro- 

 ducts or other organic compounds are attractive to blow- 

 flies when isolated, and used as baits. 



11. To see which of the meaty substances are most attractive, 

 when, and under what conditions. 



III. To experiment in a sinular way with vegetable substances, 

 to see if they are at all attractive. 



The flies used in these experiments were those which were 

 * Communicated by Prof. H. Maxwell Lefrot, M.A., F.Z.S. 



Proc. Zool. Soc— 1916, No. XXXIY. 34 



