IXJUPJOUS INSECTS. 79 



or held in check? The first is a question in systematic ento- 

 moloiry, while the other two belouiTr to economic entomologv, 

 yet investigations on tliese latter must alwa^'s follow the for- 

 mer. We can never learn from the books what has already 

 been pul)lished about an insect till we recognize its name. 

 The losses caused by the devastations of the insect tribes 

 on our productions are vastly greater than are generally sup- 

 posed. A few years ago, I estimated the loss on a single 

 crop caused by one species alone, in '^ne field during the 

 summer, to be not less than twenty-five per cent, of the 

 whole, and yet the owner was entirely ignorant of his loss. 

 Farmers consider it pretty hard times when they know 

 that they are getting only three-fourths of a crop, but if 

 they are unconscious of their loss they are comparatively 



happy. 



" If ignorance were bliss 

 'Twere folly to be wise." 



If a careful examination of any given surface, as one square 

 rod of grass field, be made as often as once a week through 

 the entire summer, one will find such a series of insects aris- 

 ing and disappearing in succession that, when he bears in 

 mind that they feed on the plants growing there, he will 

 wonder that an\'thing is left to be harvested. While careful 

 study is being made on the food of plants and the most 

 economical methods of obtaining and applying it, little, com- 

 paratively speaking, has thus far been done on the study of 

 those insects and parasitic plants which destroy so large a 

 percentage of our cultivated crops. While I would not have 

 the researches in other lines in any way abated, I would have 

 extensive researches made into the life, history and habits of 

 our insects and critical investigations on insecticides. I have 

 selected for consideration at this time a few of the insects 

 that have come under my notice in this State, and will first 

 direct your attention to the 



Ca nJcer-worms . 



There are two diSerent species of insects known under 



this name, one of which is the spring canker-worm and the 



other is the fall canker-worm. The females of both species 



are entirely destitute of wings, and so closely do they re- 



