HODGE] THE HOUSE FLY— A PRACTICAL LESSON 247 



In order to be vital the lessons must be real and to the point. 

 After arousing general interest by telling the class what flies do; 

 how in the Spanish war they wounded 20.788 of our soldiers, and 

 killed 1,380, with the germs of typhoid fever, how they kill 58,000 

 yearly with the germs of enteritis, dysentery, fly-time summer com- 

 plaint, almost all infants under two years of age, using tactfully 

 any local epidemics or cases that may suggest a lesson, develop and 

 draw out all the children know and finally call for volunteers to go 

 into the barnyards (or old straw stacks in case of the stable fly) and 

 get specimens of eggs, maggots and puparia, and with the filth in 

 which they are found, demonstrate the whole life history of the 

 insect. One teacher who did this writes: 



"Last week I had some maggots in horse manure. It was an 

 unusual thing to do in school, but I wished to emphasize the idea of 

 filth. I think it was successful, for the disgust was great when they 

 saw that they changed into flies. Poeple are so irresponsible that 

 they have to be shocked to awaken their fighting power." (This 

 can all be done in a cleanly and safe manner by putting the material 

 into large fruit jars or wide mouthed bottles. Do not fill more than 

 half full. If it is desired to keep them for several days to show 

 actual development, they may require opening to give air once or 

 twice daily, but they must be stoppered or closed tightly as maggots 

 are strong and can burrow or squeeze through minute cracks) in 

 concluding some of these experiments treat the material with a 

 solution of iron sulphate, two pounds to the gallon, or with other 

 substances recommended locally for killing the maggots about 

 stables or outhouses). 



Study with the class all the substances in which flies may breed, 

 wet decaying matter, animal or vegetable, filth of stables, rotting 

 lawn clippings, weeds or garbage, and work out practical methods 

 for each home of dealing with all such substances to prevent flies 

 from breeding in them. ^ All such matters about the farm barnyard 

 should be spread on the ground or plowed or harrowed into it 

 daily. In this way, according to all recent investigations from 

 50% to 70% of its fertilizer value can be saved to the soil, which is 

 lost by filthy, antiquated methods of storing and rotting. Even 

 in the town or city lot, by proper planning, large quantities of 

 stable refuse can be dug into the ground about trees, shrubbery or 

 grape vines, between rows of bush fruits, strawberries or com, 

 while these are being cultivated or cleared of weeds. When 

 properly spread or stirred into the surface it will become too dry 



