572 
Journal of Agricultural Research 
Vol. XI, No. ii 
It was found that in the more immune progenies both the number of 
larvae and the damage per larva were low. Since the number of larvae 
must be determined largely by the choice exercised by the moth in 
depositing eggs, it follows that the plants avoided by the moths are also 
the plants which the larvae find most distasteful. This agreement 
between the instincts of the adult insect and those of the larva is difficult 
to explain as the result of morphological characters of the plant and would 
argue that at least a part of the immunity is the result of chemical 
differences, perhaps the presence of some volatile substance distasteful 
alike to the moth and the larva. Both in California and Maryland 
during the period of the experiments the injury from corn earworms was 
found to decrease slightly as the season advanced. 
From the experiments here reported it appears that by increasing 
the length and thickness of the husk covering and reducing the husk 
leaves varieties of sweet corn can be produced in which damage from 
the corn earworm is materially lessened. No difficulty was experienced 
in securing by hybridization and selection the desired plant characters 
in combination with the seed characters of sweet corn. 
