324 Journal of Agricultural Research voi. xviii. No. 6 



we had no difficulty in maintaining fall migrants on such plants, and 

 these sexupara produced normally. The young ovipara, however, fed 

 for from two to five days and then died. It was finally found necessary 

 to transfer all the material to plants which had not shed their matured 

 leaves, and on these there was no difficulty in raising the ovipara. 



Under natural conditions it would be impossible for ovipara to obtain 

 other food than that furnished by the mature leaves. It seems quite 

 possible that the form having become adapted to such a source of food 

 should be unable to maintain the proper balance when furnished with a 

 source from which food may be obtained too rapidly or abundantly 

 and consequently could not live. 



We have been unable to find any foliage which, if still green, is too 

 hard or dry for the insects to live upon. 



