p 



1917 ENTOMOLOGICAL SOCIETY. 19 



complete its cycle on the apple. I have some sexual' females on the apple at the 

 present time that we obtained from colonies that were on the apple all year. Of 

 course I have been breeding the aphids under insoctary conditions. 



Dr. Dearness: Does it stimulate sexual development to be on the Plantago? 



Mr. Ross.: I do not know. The oviparous forms are given birth to by the 

 migrants that fly back to the apple. In working with avena; I was raiher inter- 

 ested to find that I could not get that species to remain on apple even where I kept 

 the specimens isolated, and I came to the conclusion that the migration instinct 

 was much more strongly developed in this case than in the case of malifoluc. 



Prof. Brittain: The important point is that a number of our farmers will 

 have to spray for this green apple bug. We do no spraying for this insect until 

 just before the blossoms open. Is it going to be necessary to spray for malifoVue 

 and make "two separate sprayings for the green apple bug? One of the orchards 

 in which we were spraying for this latter pest had quite a severe outbreak of sorhi; 

 but we omitted that iirst spray. We find that when we spray to control the grer>n 

 apple bug we have to give. an extraordinarily thorough application, and we fouiid 

 that such an application gave us a fair commercial control of malifolice as well, 

 though we did not destroy all of them, for the leaves curl right around them and 

 provide a fine protection. 



Q. — What spray gave you the best results against TnaUfoli(B? 



Prof. Brittain : At the time the small leaves were just about the size of a 

 teji cent piece. 



Mr. Eoss: I should like to ask Prof. Parrott if he ever recommends that 

 second spray when the blossoms are just showing pink for tho aphids. 



Prof. Parrott : I do not, Mr. Ross ; but if you study the literature on spray- 

 ing for apple aphides you will find all sorts of recommendations. If in 'New York 

 we deferred treatment until that time, a great many of the stem-mothers would be 

 missed by the application, on account of the curled leaves. I thoroughly endorse 

 what was just sard, that farmers as a rule do not spray thoroughly enough to 

 control green apple bug. Certainly they do not control malifolicD or sorbi for the 

 same reason, and that is without doubt one of the problems now before us. We 

 should encourage spraying practices that are calculated to hold the aphides in check. 



Prof. Brittain : Spraying with nicotine is expensive. With us we fre- 

 quently have to put on two applications, but if we had to put on three it would 

 ruin us. 



Prof. Parrott: I think in your case it would be worth experimenting to 

 determine if you can delay the spray. 



Prof. Briitain : In our work it is certain that we did not miss enough to 

 pay us to put on a third application, but the work was done with great care. 



Prof. Caesar: We have sometimes omitted the first application, and for San 

 Jose Scale waited until just as the pink was showing, yet obtained good results on 

 the scale without appreciable injury to the foliage. 



Mr. Winn : Mr. Eos.? states that he has specimens of these aphides. I should 

 like to know what method he takes of mounting or preserving such minute 

 insects. 



;Mr. Ross : We use 70 per cent, alcohol for preserving aphides. 



I E.S. 



