REPORT OF THE ENTOMOLOGIST AND BOTANIST. 241 



cannot be dislodged. Sinking their minute jaws into the tissues of the body of their 

 vcitim, they remain firmly attached, sucking its blood and living entirely at its expense, 

 until the full larval growth is reached. Dr. Riley thinks that the full period of develop- 

 ment of the larviB, after attachment, seldom exceeds a fortnight. When distended 

 with food, these mites are so swollen that their short legs are almost invisible, and many 

 people who notice them mistake them for the eggs of some parasite. When examined 

 closely, however, their legs can be seen and are found to be six in number, which is now 

 known to be one of the characters of the larvae of the genus of mites called Tromhidiuin. 

 As soon as the larvaj are full-fed, they let go their hold of their hosts and fall to the 

 ground, where, under some temporary shelter, they gradually change to pupse inside the 

 larval skin. Finally, both the old larval skin and the new one inside it, which incased 

 the pupa, burst, and the perfect form, an eight-legged mite, emerges. These are common 

 objects in the country, drawing the attention even of people who do not study insects, 

 by the intensity of their velvety scarlet colour. They pass the winter in the perfect 

 state, and are frequently conspicuous on the ground in early spring before vegetation has 

 made much growth. Not only is this insect useful in the larval form, when it preys 

 upon locusts, but also in the perfect state it does good service by seeking out and devour- 

 ing their eggs. 



I give below a few extracts from letters of correspondents who have noticed these 

 mites : — 



"Craighurst, Simcoe Co., Ont., Dec. 19. — We had this year the same experience 

 with grasshoppers as you mention. They hatched out in immense numbers, and at one 

 time we were afraid they would do great damage, but they seemed to disappear early in 

 August or the latter part of July. The parasite that lays its eggs on their backs under 

 the wings was abundant. Most specimens examined showed their presence." — G. C. 

 Gaston. 



" Princeton, Brant Co., Ont., June 23. — On examining some locusts or grasshoppers, 

 I find on the underside of the wings some minute insects — I suppose, parasites. They 

 are now on nearly all the locusts I have looked at. The majority are about 2V of an 

 inch in length, but many much smaller, of a bright red colour." — J. E. Richardson. 



"Doe Lake, Muskoka, Ont., August 18. — Grasshoppers damaged both grass and 

 grain. They have done much harm on light sandy soil ; there are many of the red eggs 

 under the wings. Are they parasites T — F. C. Judd. 



'■ Omemee, Victoria Co., Ont., Aug. 3. — I send you a common grasshopper, with 

 red insects on it. They appear to be very numerous this year, but I fear came too late 

 to prevent the grasshoppers doing harm." — E. S. Morgan. 



" Louise, Grey Co., Ont., September 26. — Grasshoppers came along about the 1st of 

 June in massive flocks and destroyed nearly all the hay. They were by far worst on 

 spring wheat and barley ; in fact, there was hardly any of either grain in this part. 

 Oats turned out about 10 to 12 bushels per acre. Pease were a fair crop. The hoppers 

 all disappeared about the 1st of August." — George Last. v 



"London, Middlesex Co., Ont., December 7. — I never saw grasshoppers worse than 

 in a part of McGillivray about the middle of June, but within two or three miles on 

 each side they were scarce. Where they were very numerous. I found none of the 

 locust mites ; where scarce, almost every one was infested." — J. Dearness. 



The Gray Blister Beetle. 



No account of the common parasitic enemies of grasshoppers would be complete with- 

 out some mention of the Blister Beetles, which in their larval stage prey upon the eggs. 

 During the past summer, as is usually the case in years following excessive locust presence, 

 Blister Beetles have done considerable damage to potato and bean crops and several 

 kinds of garden plants. 



" Grenville, Argenteuil Co., Que., June 11. — I send by mail specimens of a new (to 

 me) potato pest. On a potato patch 20 feet by 40 feet there were many thousands of 

 them. I was through the patch two days ago, and there was no appearance of anything 

 unusual. Now the plants on which they are feeding are almost leafless." — Robert 

 Hamilton. 



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