The European Corn Borer. 9 
the plant at practically any point, but usually enter between the 
leaf sheath and stalk (Fig. 6), or between the stalk and the base 
of the partly developed ear (Fig. 7), in case the plant has advanced to 
that stage of growth. 
Where, as frequently occurs, several or many borers are present 
within the same stalk, it becomes reduced to a mere shell, filled with 
Fic. 7.—External view of ear, showing extruded frass and numerous punctures caused 
by larve of the European corn borer. (Caffrey.) 
fragments of the frass or castings of the borers. Such injury may 
cut off much of the supply of nutriment from the developing ear and 
greatly weaken the stalk, which eventually collapses and breaks 
over. 
The ears are entered by the borers either directly through the 
silk and husk, or through the short stem or “shank” by which the 
ear is attached to the plant (Fig. 8). Here they feed upon the grain 
