CHAPTER IX 

 DISSEMINATORS OF DISEASE 



The house-fly may seem at first much less to be 

 dreaded than any one of the painfully " biting " or (to 

 be correct) skin-piercing and blood-sucking flies ; yet 

 it should be regarded as a much greater enemy to 

 humanity and a more dangerous peril than any of 

 those other flies, of which some short mention and 

 description has now been given. Its life-history and 

 its fecundity have been already alluded to ; its rapid 

 growth and maturity counterbalance the fact that it is 

 short lived. 



From ancient times there has been a consensus of 

 opinion that there was in some way a connection of 

 cause and effect between swarms of flies and the 

 spread of disease. In the plagues of Egypt, in the 

 reign of Pharaoh of the Exodus, it will be remembered 

 how, after " the land was corrupted by reason of the 

 swarms of flies," Exodus viii. 24, there came "a 

 very grievous murrain " upon cattle, Exodus ix. 3, 

 followed by a "plague of boils and blains" upon man 

 and beast. 



In our present day insect life is being scientifically 

 investigated with the view of establishing the con- 

 nection, and of discovering fully the serious r6le of 

 disseminating disease, of which the house-fly has long 



