rACKAUD.J THE WIIEAT-FLY — THE WHEAT-MIDGE. 709 



The Common WiricAT-FLY, Cldorips vulgaris Fitch. — Certain small, slender, pale- 

 green and watery-white shining maggots belonging to the above species with the oth- 

 ers mentioned below are said by Dr. Fitch to burrow in di£Eerent parts of tlie stalks, 

 dwartiug and often killing them. 



It was not until 1855 that it was known that wheat in this country 

 was affected by these maggots, when they were discovered by Dr. 

 Eitch, who thinks that it is from the number of these and other insect 

 depredators that farmers are not now able to raise such large crops as 

 used formerly to be harvested. The Chlorops vulgaris is abundant the 

 latter part of June in wheat-fields. It is pale yellow, and 0.15 inch in 

 length. Another fly is the Meromyga americana of Fitch. It is yel- 

 lowish-white and a little larger than the preceding. Another minute 

 fly, found in company with the others, is the Liplionella ohera. It is less 

 than a line in length and is jet-black. Still another form found in the 

 heads of wheat in New York in June is Oscinis tibialis. It is only 0.08 

 inch in length, and also jet-black,*j|ith pale dull-yellow shanks and 

 feet. The last fly mentioned by Fitch is Hylemyia deceptiva, which 

 occurs in abundance upon heads of wheat late in June. It is ash-gray, 

 with black legs and feelers, and a quarter of an inch in length. 



INJURING THE HEADS. 



Thk Wiieat-Midge, Diplosis tritici of recent authors ; Ccddomyia tritici Kirby. — 

 Several minute orange-red maggots, one-eighth of an inch long, crowding around the 

 kernels of wheat, causing them to shrivel and dry when ripe. The maggots descend 

 into the ground and spin minute cocoons, from which in the following June come 

 bright orange-colored midges. — (Fitch.) 



This insect was probably imported into Quebec about the year 1820. 

 It made its way along the Saint Lawrence and Chambly (Sorelle) Elv- 

 ers into Northwestern Vermont, and soon became so abundant in New 

 England and New York that the cultivation of wheat was mostly aban- 

 doned. Its attacks then decreased, and wheat was again raised until 

 in the year 1854, when wheat was largely in cultivation, it again became 

 very destructive, causing a loss in the State of New York alone, accord- 

 ing to the estimate of Dr. Fitch, of $15,000,000. In Canada, in 1856, 

 the loss was estimated to exceed $2,500,000. In the same year, in por- 

 tions of New York, the midge destroyed one-half to two-thirds on the 

 uplands, and nearly all on the lowlands, and the destruction was worse 

 in 1857 and 1858. In 1858 very little white wheat was sown in Western 

 New York, and the midge reduced the value of all the wheat-lands at least 

 40 per cent. In 1859 the midge unaccountably disappeared, to again 

 become prevalent in 1801.— (Fitch.) Mr. liiley, in the New York Tribune, 

 refers to this insect as infesting wheat in Indiana during the summer of 

 187C. 



As regards the habits of the wheat-midge, I reproduce the following 

 account from my " Guide to the Study of Insects:'' "When the wheat is 

 in blossom, the females lay their eggs in the evening by means of the 

 long retractile tube-like extremity of the body within the chafl:y scales 

 of the flowers, and in clusters of from two to fifteen or more. In eight 

 or ten days the eggs disclose the transparent maggots, which, with age, 

 become orange-colored, and, when fully grown, are one-eighth of an 

 inch long. They crowd around the germ of the wheat, which, by press- 

 ure, becomes shriveled and aborted. At the end of July and in the 

 beginning of August, the maggots become full-fed, and in a few days 

 molt their skins, leaving the old larva-skin entire, except a little rent 

 in one end of it. 'Great numbers of these skins are found in the 

 wheat-ears immediately after the molting process is completed.' 



