INSECTS 69 



responsible for horse stables should make sure that the 

 manure is thrown into screened pits and sprinkled with 

 chloride of lime at least once a week. 



Another method of dealing with the problem is that sug- 

 gested by Professor C.F. Hodge of Clark University, Worces- 

 ter, Mass. It is that of letting the flies catch themselves. 

 He has devised a simple and inexpensive flytrap, which is 

 easily attached to any garbage can (or to a window screen) ; 

 or it may be baited with bits of fish or other food. The 

 flies are attracted by the odors of the garbage or food bait, 

 and when caught may be killed with boiling water. If the 

 various suggestions are followed, even farmhouses, as ex- 

 perience has shown, may be rendered practically free from 

 the filthy and dangerous house fly. 



V. ADDITIONAL TOPICS ON INSECTS 



45. Field and library study of other insects. (Optional.) Study 

 as many of the following insects as time allows, consulting Sander- 

 son's "Insect Pests of Farm, Garden, and Orchard," Hodge's "Na- 

 ture Study and Life," National and State 

 Circulars and Bulletins, articles in Ency- 

 clopedias or other reference books. Em- 

 phasize especially 

 the habits, life 

 history, and eco- 

 nomic importance 

 of each of the fol- 

 lowing insects: 

 Colorado potato 

 beetle (Fig. 42), 

 cut worms, army 

 worms, San Jose 

 scale (Fig.43), tent 

 caterpillar, chinch 



FIG. 43. San Jose scale 

 insects on pear. Above, 

 single scale enlarged. 

 (Howard.) 



A B 



FIG. 44. A, human 

 louse ; B, eggs at- 

 tached to hair. 



