REPORT OF THE ENTOMOLOGIST AND BOTANIST. 179 



pieces of straw observed in threshing and cleaning should be carefully gathered and 

 burnt. Sometimes, as stated above, there are no galls formed, the presence of the 

 larvae causing merely slight swellings and the hard thickened condition of the straw. 

 These portions break off in threshing and many are carried through with the grain. The 

 thi'eshed straw should be examined, and if the larvae are found therein it should be 

 •destroyed either by feeding or some other consumption before the ensuing spring. 



The Grain Aphis {Siphonophora avence, Fab.). — The green, yellow, red or blackish 

 plant-lice which are frequently seen upon all the small grains are well known by most 

 farmers. These insects are found in some numbers every year and in occasional seasons 

 increase to such an extent as to cause widespread alarm. Notwithstanding this general 

 increase in numbers, it cannot be said that their attacks have ever materially decreased 

 the wheat crop of the year, for they are invariably accompanied by various parasites which 

 graduallyincreaseinnumbers andfeedupon the plant-lice until most of them are destroyed. 

 The two most numerous of these parasitic species in Canada are Aphidius granariaphis, 

 Cook, and A. obscuripes. In addition to these there are always many of the leech-like 

 larvae of the Breeze-fiies, Syrphidce, which crawl about among the colonies of plant-lice 

 and every day destroy large numbers, as they feed entirely upon plant-lice. 



The Grain Aphis multiplies with great rapidity and the insects may be found of all 

 sizes and colours all on the plants at the same time. The females bring forth living 

 young continuously and these young lice are in a few days full-grown and themselves 

 begin to propagate in the same way. There are no practical artificial remedies which 

 oan be applied on a large scale to fields of grain. 



The Wheat-stem Sawfly {Gephus pygmceus, L.), treated of at length in my 

 report for 1896, has only been mentioned by one correspondent. 



"Buffalo Lake, Moose Jaw, Assa., March 3, 1898. — I send a few heads of wheat 

 «uch as appeared in one of my fields last year. This field was hailed out in 1896 and 

 having been sown on summer-fallow the straw was burnt as it stood in the spring of 1897. 

 A week or two previous to cutting, I noticed a great many straws and heads like those I 

 •enclose scattered loose among the grain, fully 5 per cent of the crop. You will notice 

 that the heads were well developed at the time. Is this the work of the Wheat-stem 

 Sawfly ? "—[George S. Tuxford.] 



It may be hoped, I believe, that the attacks of this insect upon grain will be only 

 -of an intermittent nature, for where the insect was abundant at Souris, in Southern 

 Manitoba, no appearance of it has since occurred. Mr. J. Wenman writes me again this 

 year that he has not heard of nor seen any trace of the insect since 1896. In company 

 with Mr. Angus Mackay, I examined carefully the wheat fields around Indian Head, 

 where I had collected specimens in 1895 and at the date the mature insects should have 

 been flying, but although the standing grain was swept with a collecting net at all times 

 •of the day and in several different localities not a single fly could be found. 



Cutworms in grain. — Occasionally considerable harm is done in grain crops by 

 •cutworms. There are several grass-feeding species in this large family which are liable 

 to attack cereal crops. The injuries to Indian corn are well known and can be prevented 

 to a large measure, but when a field of the small grains is attacked the only recourse is to 

 adopt some agricultural treatment founded on the known life-history of the depredator. 

 The exact identity, then, of the species is of importance, so that the life-history, if 

 recorded, may be used as a guide to escape loss. An instance of the value of such 

 information is found in the following correspondence : — 



" Carleton Place, Carleton Co., Ont., May 26. — We send a box containing some 

 cutworms. They have destroyed two fields of our oats. What can be done to prevent 

 them from destroying all our crop ? Would spreading lime over the field kill them, and 

 how long will it be until they have passed away, so that it will be safe to sow some 

 other gi-ain or to plant corn on the fields where they ate the crop off 1 " — [J. Yuill & Sons.] 



Reply : " Your letter of the 26th inst. containing cutworms from your oat field 

 came to hand, but the cutworms had eaten each other until only one shrivelled up bitten 

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