INTRODUCTION xvii 



able as perpetuating in some degree the old ideas. 

 Strictly speaking, the term 'typhoid fly' is open to some 

 objection as conveying the erroneous idea that this fly 

 is solely responsible for the spread of typhoid, but, 

 considering that the creature is dangerous from every 

 point of view and that it is an important element in 

 the spread of typhoid, it seems advisable to give it a 

 name which is almost wholly justified and which con- 

 veys in itself the idea of serious disease. Another 

 repulsive name that might be given to it is 'manure 

 fly,' but recent researches have shown that it is not 

 confined to manure as a breeding place, although per- 

 haps the great majority of these flies are born in horse 

 manure. For the end in view, 'typhoid fly' is consid- 

 ered the best name." 



As a matter of fact this name has been adopted very 

 generally. The newspapers took it up with avidity, 

 and during the summers of 1909 and especially of 

 1910, many good journals conducted a constant ed- 

 itorial campaign, almost every issue during the sum- 

 mer months containing some reading matter calling 

 attention to the danger of the creature and the ne- 

 cessity of fighting it. It is undoubtedly true that peo- 

 ple will fear and fight an insect bearing the name "ty- 

 phoid fly" when they will ignore one called the "house 

 fly," which they have always considered a harmless 

 insect. So to gain the practical end the retention of 

 the name "typhoid fly" seems by all means to be ad- 

 visable. The only substitute suggested in the two 

 years since this term has been adopted which ap- 



