68 Ohservatlous on the Habits of Certain Flies 



A clean cottage had no flies, whilst one, to which it was attached and 

 which was less clean, had many M. dotnestica. No flies were found on 

 November 29th in a cottage, in which there had been large numbers on 

 the 6th. 



M. domestica was, therefore, found in largest numbers in town and 

 in the country in the neighbourhood of horse manure — in the latter case 

 in and about farmyards and buildings and in warm kitchens of farm 

 houses. But the numbers were found to decrease markedly when isolated 

 houses in the country or manure heaps far from buildings were examined. 

 In farmyards and manure heaps far from buildings in the country such 

 genera as Stomoxys, Scatophaga, Borborus and Limosina predominated. 



M. domestica was observed alive in town as late as December 2nd 

 outside, and December 9th inside; in the country as late as December 4th 

 both outside and inside in 1916. In 1917 a house-fly was caught in a 

 house in a village in Cambridgeshire during the last week in December, 

 so that it is probable that those seen in that month in 1916 lingered 

 sometime longer, but the places were not revisited in that year. 



Observations on a Horse manure heap in Summer. 



Observations were made on the temperature generated in a horse 

 manure heap; the number of flies emerging therefrom; its attraction for 

 adult flies and power to nourish their larvae after fermentation; and on 

 a preliminary trial of the effect of an application of creosote oil mixture 

 (see Forman and Graham-Smith (1917), pp. 123-199). 



From July 31st to October 21st, 1916, three separate experiments — 

 A, B, C — were carried out; each dealing with about 6 cwt. of horse 

 manure, which was one day's accumulation from a stable in Cambridge. 



The manure was, in each case, made into a heap in a specially pre- 

 pared enclosure; and daily observations were made on temperatures 

 recorded at certain points in the heap, on the number of flies emerging 

 from it and the time of their emergence. 



Experiment A dealt with 6 cwt. 1 qr. manure, and lasted from July 

 31st to August 14th. The manure was thrown into a loose heap. Experi- 

 ment B dealt with 6 cwt. of manure which was tightly packed, and 

 lasted from August 31st to October 29th. Experiment C dealt with 

 5 cwt. 1 qr. manure, which was loosely thrown up as in A but treated 

 " incrementally 1" with 1225 c.c. of creosote oil mixture. It lasted from 

 September 18th to October 21st. 



' 'rhi.s term implies that the manure was Hj>rea(l uiit in a tliin la\'er upon tlio ground 

 and the fluid then .sprayed evenly over its surface. 



