H. Eltringiiam 453 



E.rji('ri)H('ii/ XV. On Auuiist 21th Heap 5 was again started with 

 fresh horse maniii'e from the adjoining stable. On August 30th the heap 

 was closed in. Some of the manure in this heajj had been purposely 

 exposed for five or si.x hours close to the door of the stable where several 

 M. donie.slira could be seen flying about. On September 3rd the traps 

 of this heap were cleared and found to contain 6 M. doniedicn. Cleai'ed 

 again on September 7th, 5 were taken. Up to September 10th no 

 more files emerged. Two CuUiiihorn efi/lJuvcephnh were found in the 

 side traps. 



Experimenl A' TV. A wooden trap covering an area of about 9 square 

 feet was placed in various positions on the permanent manure yard at 

 the farm for 2 or 3 days at a time. In several cases no flies of any sort 

 were caught, but in one position, at date about August 30th, it captured 

 16 M. domesiica, 2 S. calcitrans, and 1 F. canicidaris. Allowed to 

 remain in the same place for several days longer no further flies were 

 obtained. 



Experiment XV II . A (juantity of pure horse manure whicli had been 

 sent to the laboratory for experimental purposes other than in con- 

 nection with flies was found to have become infected in two or three 

 days and contained many larvae of M. doinesfica. This material, in 

 cprantity about a bucketful, was covered over with a box trap. 

 Examined from time to time the larvae apparently thrived but they all 

 disappeared by the beginning of September, and by September 10th 

 no flies had emerged. The slow development was doubtless due to the 

 perfectly cold conditions owing to the small cjuantity of manure. 



Experiment XVIII. At a cottage near the farm buildings it was 

 found that the kitchen and garden refuse were placed in a pit in the 

 ground some 20 or 30 yards from the house. When examined this pit 

 was sodden with water and very offensive. Great numbers of flies were 

 buzzing about it, though M. dotnestiea was not in evidence. L. caesar 

 was perhaps the commonest fly observed. A box trap was placed over 

 a part of this ruljbish pit and flies taken from time to time. In about 

 a week some 78 flies were captured but only 1 example of M. douiestica 

 was included. The totals were as follows: 



Musca doniestica L. ... ... 1 



Hydrotaea dentifes F. ... ... 22 



Eristalis teriax L. ... ... 3 



Erist.alis arbustoniin L. ... ... 4 



Syritta pipien.s L. ... ... 11 



Ophyra leitroctoma W. ... ... 13 



