14 THE ECONOMIC ASPECTS OF ENTOMOLOGY. 
labour to diagnosing genera and species, and arranging 
specimens; and wholly omit from their studies the habits of the 
creatures, or their influences upon industrial pursuits. 
Setting on one side the insects which are instrumental in 
injuring the flower-garden, and marring the work of the 
most skilfulesthetic gardeners, there are a vast number of others 
which arrest or prevent the growth of timber and shade trees, 
injure our fruit crops, lessen the productiveness of or absolutely 
destroy field-crops, such as cotton, indigo, turnips, potatoes, 
liquorice, tea, coffee, chicory, the vine, the cocoanut palm, and 
other cultural industries upon which depend the prosperity of 
entire communities. In saying this, I merely state what is but 
too well known to all who are engaged in the cultivation of the 
soil; but when I add that in other parts of the world there are 
known and are applied remedies which are either wholly or par- 
tially successful, I state what is known to but comparatively 
few of the many concerned. The attacks of insects are largely 
influenced by conditions of season, quantity and periods of rain, 
combination of rain, and heat or cold, and other climatic phases. 
We cultivate the soil, and we sow or plant with industry and 
intelligence, and if the fates are propitious we reap the products 
of our industry. The absence of sufficient rain might be largely 
compensated for by irrigation, and in these directions also we 
fail to avail of the assistance which nature is prepared to afford 
by yielding her underground waters to render fruitful the 
surface of the earth. In this case, the small cultivator is 
mainly deterred by the costliness of the appliances and want of 
knowledge how to utilize them; but as regards insect enemies, 
he seems to be content to remain in ignorance of a vast deal of 
knowledge that exists upon the subject, and to trust wholly to 
the chapter of accidents. 
There is a great deal of practical literature upon the various 
phases of economic entomology, which might be collected from 
among English-speaking communities; and I cannot but think 
