1d83ea69___Publications___UGA_Extension__Symptom_s__of_Damage
[Insect] Flea beetles [Description of insect] The corn flea beetle is about the size of a pin-head (1/16 inch) and is black; strong jumper. [Symptom(s) of Damage] 
Irregular brown lines or "tracks" scratched from the top layer of leaf tissue; severely damaged plants turn silvery, may wilt and die.
Georgia Corn Diagnostic Guide | Publications | UGA Extension
Symptom(s) of Damage