*8 THE BOOK OF THE FLY 



breed swarms of flies. Though such is not necessarily 

 the case, the liability by common carelessness is very 

 great. 



The expert horticulturist has a special preparatory 

 treatment for fresh manure intended for hot-beds ; new 

 manure in heaps rapidly "heats," and is aerated by 

 being turned over two or three times on separate days 

 before being packed close for the hot-bed. This 

 process of treatment rather disagrees with the breeding 

 of the house-fly. Mushrooms and all the fungus tribe 

 breathe by inhaling oxygen and exhaling carbon di- 

 oxide ; and so it happens that even insects which 

 delight to feed on mushrooms, are somewhat repelled 

 by the special atmosphere of very actively growing 

 mycelium or spawn. 



The amateur entomologist and the nature-student 

 will observe that the flies which pester the gardener at 

 work are mainly other than the common house-fly. 

 The reader, nevertheless, will like to know if something 

 more cannot be done to stable manure for exterminat- 

 ing maggots, whether of house-flies or the many various 

 filth flies, already hatched and growing therein. Well, 

 " something" indeed can be done by the use of some 

 insecticide. Hitherto chloride of lime has been em- 

 ployed, but the most approved insecticide for the 

 purpose is a solution of iron sulphate two pounds in 

 one gallon of water ; this is said not to deteriorate 

 the horticultural value of stable manure. However, 

 in fine weather, the spreading out and drying of freshly 

 received manure practically rids it of fly maggots, which 

 cannot survive this simple procedure. The mere burial 

 of fly-blown dung and stable litter without prior treat 



