CHAPTER XII 

 THE SERVICE AND UTILITY OF FLIES 



It is often asked have not house-flies some use in 

 Nature ? The only true answer is that they are warn- 

 ing signals. 



They certainly do join with a multitude of other 

 flies in promiscuous scavenging services, and they can 

 be very active agents therein ; but this w-ork only 

 aggravates the fact of their dangerous partiality to 

 mankind, together with all his belongings and sur- 

 roundings. These creatures may well be imagined to 

 have developed out of some primaeval species by reason 

 of the increase of mankind upon this planet. The mere 

 presence of the house-fly denotes some nuisance more 

 or less remote ; the local density of the brood indicates 

 the degree and the proximity of unsanatory conditions. 

 Under present circumstances the visitation of the 

 house-fly is Nature's intimation that peril of a very 

 insidious character is about. Very properly, Nature's 

 messenger will not be denied, and pertinaciously mani- 

 fests herself to us indoors ! 



It has already been explained that the scavenging 

 service of the house-fly can be altogether dispensed with, 

 inasmuch as there is a sufficiency of other less noxious 

 flies and creatures devoted to such work. Reflecting 

 on the Story of Creation, and the mission of man as 



