December, '09] JOURNAL OF ECONOMIC ENTOMOLOGY 463 



NOTES ON TWO INSECTS FOUND ON CORN 

 By R. L. Websxer. Ames, loica 



In some notes made during last year, 1908, I find that two insects 

 are mentioned as being found on corn, the occurrence of which I have 

 been unable to find any other record. Since the two species are not 

 mentioned in the 18th or 23d reports of the Illinois State Entomol- 

 ogist (Forbes Corn Insects) it may be worth while to record the fol- 

 lowing data : 



Hemerocampa leiocostigma S. & A. A nearly mature larva of the 

 whitemarked tussock moth was found on a corn leaf in a field of corn 

 near the college on August 31st. The leaf was partly eaten when 

 found, and the larva continued to feed on it after taken to the in- 

 seetary. The larva completed its transformations and a female moth 

 emerged September 21st. 



Aphis setaria;, Thos. On July 1st a winged form of this species was 

 found on a corn blade in a field near Ames. The aphid had produced 

 several young, all of which were brought to the insectary and placed 

 on a com plant. These, however, died within a few days. 



On July 7th I found both winged and wingless adult forms on 

 blades of corn, of which two the winged form had several young 

 beside it. These specimens were placed upon corn in the insectary. 

 On the same day Mr. C. E. Bartholomew brought in winged and 

 wingless forms of Aphis setarice Thomas, which were at that time very 

 common upon plum. A comparison between the aphids on the corn 

 and those on the plum showed them to be the same. 



In the insectary these aphids failed to live upon corn for any length 

 of time. In the field they were found but sparingly, and always with 

 very few young in the colonies. The fact that apterous adults were 

 found on corn indicates that the species is able to live upon that plant 

 long enough to attain maturity. Later in the season Aphis setarice 

 was found common on Setaria glauca and Panicum crus-galli, as well 

 as upon plum, in the vicinity of Ames. 



Diabrotica longicornis Say. While on a field trip in the northern 

 part of the state in September this year I spent some time looking for 

 the beetles of the northern corn root-worm, which is practically un- 

 known in that part of the state. After an hour's search in a cornfield 

 in northern Kussoth County, Iowa, I found a single adult within a 

 quarter of a mile of the Minnesota line. I believe that the species 

 has not been recorded in Minnesota. 



