SUMMER MEETING. 89 



This mite is quite light in color, and about as large as the newly hatched 

 louse. It cau be readily distinguished from the latter by its four pair of legs, 

 unless it is in the larval or six-legged state and then it can be distinguished by 

 having its third pair of feet a considerable distance back of the second pair, 

 while the lice have their three pairs of feet near together. 



I have no doubt but what mites do much more good than they get credit for 

 by devouring the eggs of insects. 



In closing I will speak of a beneficial species, Trombidium sericum, belong- 

 ing to the same family as the red spider. This is a very pretty red mite, hav- 

 ing a velvety appearance, and measuring nearly an eighth of an inch in length, 

 and has long been known to be very useful in keeping the grasshoppers in check 

 by preying upon their eggs. Mr. C. M. Weed, of the Illinois University, re- 

 ported this mite as very destructive to the grasshopper eggs in that State last 

 spring, and it must be doing the same kind of work for us. 



The benefit that many of the mites aud insects are to man because of their 

 habits of preying one upon another can hardly be overestimated. The earth 

 would be a most miserable dwelling place for man, if, indeed, it would be in- 

 habitable at all, if a few of our insects were left unmolested to propagate their 

 kinds. Many of thetn lay their eggs by the hundred, and produce two or three 

 broods in a year. At this rate insects would soon become so numerous as to 

 destroy every living thing; but the fact is they are only able to hold their own. 

 What, then, are the agencies to so effectually keep in check the increase of 

 insect life? It is, upon one hand, the food supply, and upon the other the 

 terrible struggle for existence that is continually going on. A striking illus- 

 tration lies in the fact that last summer there was hardly a tree or shrub in 

 this vicinity that was not infested with bark lice, and some to such an extent 

 that it seemed they would surely be destroyed. Last fall I removed several 

 hundred scales from infested trees, and found over 80% were parasitised, and 

 this summer Prof. Cook looked in vain for live scales to show his class. So 

 wheu we breathe out curses against the mites and insects that do us harm let 

 us not forget to count the benefits that come from the same sources. 



INSECT MISCELLANY. 



Prof. Cook, in reply to a question, said that the plum curculio had but a 

 single brood in a year, though it continued to make its appearance until late 

 in the season. 



Mr. Hewitt: Does the curculio live upon anything besides the plum? 



Prof. Cook: Yes, on the cherry, peach, pear, quince, and apple. I have 

 found as many as 70 per cent, of the latter with its crescent mark. It does not 

 cause these other fruits to drop as it does the plum. Some one asks if it will 

 then be of much use to destroy the fallen plums when these other fruits are 

 near? Probably not. 



A. G. Gulley: With us it is necessary to jar the trees the whole season, 

 though we get fewer from the middle of June to about the tenth of July. 



C. A. Sessions: We in Oceana county also find them numerous again in the 

 latter part of the season aud had supposed that there was a second brood. 



C. D. Lawton: We obtained plums by the use of Paris green and kerosene. 



Prof. Cook: Kerosene preparations have had no effect on the curculio 

 with us. 



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