During the third week of July, 1952, adults of the tarnished plant bug, Lygus lineolaris P. de B. [–L. oblineatus (Say)], suddenly became very numerous in a field of young cucumber, variety straight Eight, near Ottawa, Ontario. The insect fed voraciously, attacking the tender, terminal growth of the vines. Little distortion of the foliage resulted, but numerous holes appeared in the leaves when they expanded.