304 EXPERIMENT STATION—BULLETINS. 



on a head or kernel to blast it, and just how effective the remedy is, and 

 how serious the damage of its application will be to the plants. 



INCORRECT NAME. 



The name "green midge," which is going the rounds of the papers, is 

 very incorrect, and should not be used. The Hessian fly and wheat midge 

 are very different insects. These midges are two-winged flies, whose larvae 

 are footless maggots. They belong to the great two-winged fly order, Diptera, 

 while these are plant lice, or aphides, and belong to the order of bugs, or 

 Hemiptera. Let all speak of this as the grain aphis, or plant louse, and 

 not as the green midge, which is entirely wrong, as they are not always even 

 green in color. 



A. J. COOK. 



June 27, 1889. 



NO. 51— ZOOLOGICAL DEPAKTMENT. 



ENEMIES OF THE WHEAT APHIS. 



The importance of parasitic and predaceous insects in overcoming our 

 insect pests, has long been recognized by the practical entomologist. He 

 sees the destroyers swept off as by a flood ; and sees in these prolific friends 

 the easy solution of the problem of insect years. He knows that were it not 

 for these friends, the destroying hosts would make our earth a desert, and 

 replace plenty with famine. He knows that adversity among these tiny 

 helpers means success to the swarms of insects that devour the crops, and so 

 is rejoiced when he see these little helpers active and numerous. 



The present season has furnished a vivid illustration of this important and 

 interesting fact. Ten days ago, June 30, the heads of wheat were crowded 

 with hungry aphides, or plant lice. These myriad lice, often five or six 

 around a single kernel of wheat, and two hundred on a single head, were 

 sucking the sap and very vitality from the forming kernels. They were rap- 

 idly blighting the grain, and unless some friendly hand were raised against 

 them the wheat crop wouid be utterly ruined. Even then, when the lice 

 were countless in numbers, and when the winged forms were rapidly spread- 

 ing to the oat fields, the hand of deliverance was easily discerned in the com- 

 paratively few but wondrously prolific enemies of the lice which had already 

 sounded a halt in the march of destruction. A week later and the enemies of 

 the lice were in the ascendency, and to-day the lice are nearly exterminated, 

 and the wheat crop is rescued and the oat crop saved. Close observation 

 easily demonstrates these truths. Even the careless eye can see the savage 

 insects dining on the lice, or the fatal egg laid which dooms the louse which 

 receives it. 



