416 SELECTIONS FROM ADDRESSES. 



This necessity, to a great extent, exists at this present moment. 

 Our farmers, as a body, with all their general intelligence, and 

 practical wisdom, have but little knowledge of that department 

 of animal life, which is so closely connected with their pur- 

 suits. The insects come, sweep over their fields like a devour- 

 ing army, and disappear; but whence they come, and whither 

 they go, and what are the means to be adopted to prevent their 

 reappearance, are subjects too frequently hidden in total dark- 

 ness. The want of scientific observation, and scientific knowl- 

 edge, on this subject, is so great, that the people have no lan- 

 guage to describe intelligibly what they have seen, and what 

 they do know. They speak of worms, and bugs, and caterpillars, 

 and butterflies, in language which, unless you know beforehand 

 what particular insect, or iv hat particular state of the insect, they 

 are describing, conveys to you no definite knowledge whatever. 

 This want of knowledge, too, leads them sometimes to adopt 

 measures to destroy the insects, and preserve their vegetables 

 and fruits, which frustrate the very object they have in view. 

 A singular instance of this occurred in my own neighborhood, 

 a little more than a year ago. Three of my neighbors, — one 

 a professed florist, another engaged pretty extensively in the 

 nursery business, and the third a mechanic, — passed my house, 

 one after the other, on two successive days. I happened to be 

 out, and gave the " good morning " to each. In the few words 

 of conversation which passed between us, each mentioned, in- 

 cidentally, the feat he had recently been performing, to save 

 his young trees from the insects. Each had found, among the 

 plant lice by which his trees were infested, a great number of 

 insects, as he expressed himself, which he had never before 

 seen. These he had very courageously killed, thinking that 

 he had thereby done so much towards saving his trees from the 

 ravages of the insects. Now it happened, that these insects 

 killed, were the very friends they should have welcomed with 

 joy. They were the carniverous larva), or caterpillars, of the 

 coccinellffi, or lady-birds, whose mission was not to devour the 

 leaves of the trees, or the plants, but the plant lice. Thoy 

 were one of nature's checks and balances, which my neighbors, 

 until then, did not know how to appropriate to their own ad- 

 vantage. 



