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SCHOOL ENTOMOLOGY 



used very successfully, especially in the Northwest and in 

 Canada. One part of Paris green is mixed with 100 parts of 

 horse manure by measure. Enough water is added to make 

 the mass soft without being sloppy. The mixture is scat- 

 tered over the fields from a wagon or stone-boat with a 

 paddle. In Minnesota a similar mixture has been found 

 cheaper and more satisfactory. It is made of one pound of 

 arsenite of soda, 120 to 150 pounds of horse manure and one 



FIG. 171 The Price oil-pan or hopperdozer, with partitions to prevent 

 slopping. (After Riley.) 



pint of cheap molasses. Dissolve the arsenite of soda in 

 water and then add to the manure, stirring well. 



140. Grain Aphides.* The English Grain-aphis,^ the 

 most common aphid affecting wheat and other small grains, 

 is a large green species which occasionally increases so rapidly, 

 just as the heads are ripening, as to injure seriously the 

 quality and weight of the wheat. The wingless females are 



* Family Aphididce, see page 66. 

 f Macrosiphum granaria Buckton. 



