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entirely protect crops from injurious insects, nor would it very likely be for the best 

 interests of agriculture, for insects have a definite mission to perform in nature, and 

 any interference with the laws of nature must be done with extreme caution — 

 insects act as Nature's pruners, preventing too luxuriant a growth of wood or foliage 

 or too profuse a jDroduction of fruit. 



The practical entomologist endeavours to find remedies which will prevent as 

 much loss as possible, and this, at the least expenditure of time and money. To 

 attain this end he finds that the knowledge of most use is that which teaches him 

 the life-history of the different insects to be studied. By this means he knows at what 

 stage of their development his foes may be most advantageously attacked. By this 

 knowledge, too, the eyes of the farmer are frequently oj^ened to the fact that insects 

 which he supposed were injuring his crops, were present as friends preying upon his 

 enemies. It would be bad taste on my part to occupy more than a few minutes of 

 your time to-day. J know that you have more papers presented than can possibly 

 be read. I shall, therefore, merely direct your attention to some of the best methods 

 of treating insects injurious to fruits, which have been developed during the last few 

 years, and I have no doubt that some of the practical orchardists and fruit-growei-s 

 present, whom I know to have used these methods, will, by giving their experience, 

 cany the point I wish to make far better than if I were to read an elaborate paper, 

 which, perhaps, might tire you. I have stated that a knowledge of the life-history 

 of Insects is of very great importance when we wish to check their ravages ; for not- 

 withstanding the enormous number of insects, there being no less than 25,000 

 described species in North America, it is only a small proportion of these which 

 need be studied by the horticulturist, and the number of first-class pests, with whose 

 habits he should be familiar, or which, at any rate, should be known by name, so 

 that information may be asked for in a definite manner, is much smaller than the 

 number of names of the varieties of any of our truits. Further than this, he will 

 find upon examining the subject that the injuries committed by insects upon his fruit 

 crops are susceptible of classification, so that they be sucessfully treated by the 

 modification, according to circumstances, of three or four standard remedies. The 

 reason of this was stated in my Annual Eeport for 1885, as follows:— 



"If you examine a large number of diff'erent insects you will find that they all 

 may be roughly divided into two large groups, by the form of their mouth parts. 

 These two groups are: 1. Those which possess jaws, by means of which they con- 

 sume the substance of their food; and (2) Those which have instead a hollow tube, 

 by means of which they suck up their food in the shape of liquid juices. Now, it is 

 apparent that for insects of the first group, as the Colorado Potato-Beetle, which con- 

 sumes the M^hole substance of its food-plant, all that is necessary is to apply to the 

 foliage some poisonous material, which will not injure the plant, but which, being 

 consumed with the leaves, will destroy the insects devouring them. Such poisonous 

 materials we have in the various arsenical compounds which I shall mention later. 



"For the second group, however, which do not masticate their food, these 

 remedies are useless, for the insects having their mouth-parts in the shape of a 

 hollow tube, as we find in the Aphides, or plant-lice, can pierce through these 

 poisonous applications on the surface of their food and extract the juices upon which 

 they live from the interior of the leaf. With such insects it is necessary to make 

 use of remedies which act by mere contact with their bodies, and do not require to 

 be eaten at all. Foi- this purpose, coal oil (petroleum) and carbolic acid, as well as 

 the vegetable insecticides known as Hellebore and the Persian and Dalmatian insect 

 powders, and tobacco, are most useful. These I'emedies, too, as they will destroy all 

 insects, are of much wider application than the poisons mentioned above." 



Methods of treatment known as preventive remedies are those by which 

 substances are applied to crops to prevent the female insects from laying their eggs 

 upon the plants which it is desired to protect. Under this head come such remedies 

 as putting alkaline washes upon the trees to prevent borers, and the application of 

 kerosene emulsion or sand saturated with kerosene around cabbages or upon onion 

 beds, to prevent the attacks of the root maggot. The class of remedies, however, to 



