100 TRANSACTIONS OF THE ILLINOIS 



all the forces within our knowledge into combined and harmonious 

 action, that the greatest and best results can be obtained. 



DISCUSSION ON ENTOMOLOGY. 



Mr. McWhorter — With regard to the canker worm, my friend, 

 James Smith, of Iowa, had large experience, and he told me that the onl)- 

 remedy he had succeeded with was putting coal tar at the root of the 

 tree, to prevent the ascending of the female moth. He put it on the 

 bark, right around the root. I went to look at the trees, and I thought 

 I could see some evidence tliat the trees had been injured by the coal tar. 

 He said they might have been, but he did not think it was as much as 

 they would have been injured by the canker worm. 



A Member — I would like it described. 



Mr. Riley — It is of a green and brownish color, and sometimes 

 black, from one to one and a quarter inches long, and having but four 

 legs it always loops in walking. The moth is peculiar, from the fact that 

 the female has no wings, and must climb up the tree ; hence the remed}' 

 mentioned is evidently a good one, though I should not advise it, as there 

 are many other remedies which are good, not now necessary to describe. 



I would make these remarks on the paper just read. From the fact 

 that Dr. Le Baron is older than I am, and that he is not present to 

 discuss the points taken more fully, I shall not enter minutely and gener- 

 ally upon an examination of them. A few, however, should be noticed. 

 I have, perhaps, traveled around the country, within the past year or two, 

 more than Dr. Le Baron has, and consequently my opportunities for 

 observation have been in some measure greater than his. 



In stating that the natural enemies of the Colorado i)otato bug have 

 been of little use, I think he is entirely wrong ; for notwithstanding that 

 it holds its own, it does not increase. These enemies have increased 

 greatly, until at last they do keep it down, much more than they did 

 five or six years ago. 



Then, again, though his classification of insects is a very good one, 

 yet it is not at all reliable as a fixed rule of classification. We must not 

 forget that an insect which this year would be set down as of the fourth 

 class, might next year be set down as first class. The queen aphis is not 

 mentioned in the category, and so again the raspberry root borer is not 

 mentioned. Moreover, what is first class in one portion of the country 

 will not be so in another ; so that we cannot avail ourselves of the classifi- 

 cation. 



Now, in relation to the horse bots, I have had too much to do with 

 them to acknowledge that they are not a great injury to the horse, and I 



