FAEMEES' INSTITUTES. 173 



same proportion. If it sliould become extinct in any locality it would be easily 

 introduced from adjoining territory, for our whole land is becoming almost a 

 continuous orchard from one extremity to the other. 



We see how this principle of amount of food has worked in the case of the 

 potato beetle. When man had planted the potato near enough to its original 

 home in the Rocky Mountains, it found the food thus introduced exactly suited 

 to its taste, and immediately showed us its wonderful power of increase under 

 favorable circumstances ; and it has traveled the bridge of potato tops that it 

 found extending eastward from the great plains of the west, till it is waiting a 

 chance to take passage to fresher fields on the other side of the Atlantic. For- 

 tunately, its enemies are numerous, and Paris green is a sure remedy when 

 faithfully applied. 



Another instance of the amount of suitable food influencing increase is that 

 of the grape-vine phylloxera. A native of this country, it unfortunately found 

 its way to France, where it has increased with wonderful rapidity, and been the 

 occasion of untold ruin to the vineyards of that land. As its food increases in 

 our own land it is becoming quite destructive ; but its natural enemies will 

 probably have little difficulty in holding it in check. 



I have spoken sufficiently of the aids which nature has provided in the way 

 of parasites. Another important aid to man for the suppression of his insect 

 enemies is many species of birds. Robbins, blue-birds, black-birds, and crows 

 for the cut-worm and white- grub, and the wood-pecker for the borers. I have 

 in my possession specimens of the wood-pecker's work in extracting borers from 

 the oak. They never fail to strike the right place. If mankind were not such 

 liereditary enemies to the birds, I think these same wood-peckers might be 

 taught sufficient confidence in their friends to learn to peck the borers from our 

 fruit trees every year. 



There are, however, two sides to this bird question. We need to observe 

 closely the habits of all in order to decide which are our helpers in the war 

 against the destructive insects. It will not do to jump at conclusions. A few 

 years ago I vowed vengeance upon a flock of crows that were busily engaged 

 every day in my corn field. I supposed they were pulling up all the corn. Upon 

 investigation, however, I found they were digging out the cut-worms, and 

 in no case that I could find had they disturbed a single kernel of corn. I have 

 seen them at work in the same manner in a field of oats just up. In the same 

 way we may find that many species of birds that we think are unmitigated nui- 

 sances are really of great benefit to us. 



In closing this essay, I will say that with all the aid nature gives us by means 

 of the parasites and the birds, we can only be successful in the war against our 

 insect enemies by united, harmonious action. One man in a community will 

 have little effect ; but if we all work with a will for the accomplishment of a 

 given purpose, and that purpose the extermination of our insect enemies, success 

 is certain. 



Following Mr. Satterlee's paper ensued a short discussion, as follows : 



Prof. Cook. — I most heartily concur with Mr. Satterlee in the use of white 

 helebore for currant Avorms, and believe that no man can afford to allow the 

 worms to denude his bushes at the present price of the remedy. I prefer to 

 apply it with water, as Paris green is often applied. I wish to make one slight 

 criticism wpon a single thing in the paper. Mr. Satterlee spoke as though the 

 curculio could be exterminated if all the fruit upon which it preys could be 

 removed one year. Perhaps this may be so, and yet Mr. Ransom, of St. Joseph, 



