84 STATE HORTICULTURAL SOCIETY. 



sene in suspension while the application is being made. Kerosene must be 

 used with care, however, as it is injurious when not judiciously employed. 



Turpentine, a vegetable substance, is said to be better than kerosene, while 

 its effects upon the plants is not injurious. It is mixed with water in the same 

 manner and same proportions as the kerosene. A suds made from whale-oil 

 soap is one of the best liquids that can be applied, but its disagreeable odor 

 makes it a very undesirable material to apply, espe iially upon house plants, or 

 near the dwelling. The odor is of such a character that it ought to extermi- 

 nate the lice, even though the material possessed no other mortal element. 

 Sulphur in soluble form is said to be exceedingly destructive to insect life; but- 

 most of the compounds in which we get it in solution are much more offensive 

 to the sense of smell than the whale-oil soap, and the strength of the material 

 is difficult to retain. Sulphide of ammonia and sulphureted hydrogen are 

 forms of sulphur in combination, the names of which recall to the Freshman 

 college student unhappy experiences,' and to the repulsive character of which 

 he can readily testify. These are, therefore, unfit to recommend as insecticides- 

 for general use. 



After all the efforts made to find an insecticide that will be most effectual 

 and convenient for the extermination of plant lice we must conclude that only 

 those of vegetable origin can be relied upon, and it is to the vegetable world 

 that we should look for the most effectual means of getting rid of this pest. 

 It is probable that nothing more effectual than tobacco smoke will ever be 

 found, and where it can be confined by any means, and its effective properties 

 as an insecticide secured it should be used in preference to any other material. 

 Pyrethrum powder, as previously stated, comes next, and is the most desirable 

 for use upon window plants. But for trees and out-door plants the subject of 

 what to apply and how to apply it is still a subject worthy of consideration and 

 investigation. Thus far many of the materials recommended are too expensive 

 to use, too difficult to apply, or too liable to injure the tender growth of the 

 young leaves and branches. There is nothing to be gained by recommending 

 a great variety of insecticides. What we want is a knowledge of the best and 

 cheapest materials for the purpose; and if these few notes awaken a discussion 

 which shall elicit the information desired their purpose will have been happily 

 subserved. 



Prof Cook: It is not always the great things of this world that make the 

 most disturbance. We have in the diseases which infest our plants an illustra- 

 tion of the dire effects of little plant growths too small to be seen by the 

 naked eye. In the life with which the entomologist has to deal we also find 

 abundant illustration of the amazing destructiveness of animals too small to 

 be seen without a microscope. It is upon one group of these "small fry" that I 

 have invited Mr. 0. P. Gillette to talk with you to-day. He will discuss the 

 subject of 



MITES. 



My subject, small as it may sound, is, nevertheless, a mitey one, and deserves 

 more attention than scientists of this country have been wont to give it. 



The mites deserve attentiou, not only because they are exceedingly interest- 

 ing objects for microscopic study, but because our comfort, our health, and our 

 pocketbooks are affected by them. They are often the " little foxes that spoil 

 the vines," and they escape unsuspected because unobserved. If they are 



