Tests conducted in a wind tunnel indicated that 10-day old Catolaccus grandis females were significantly attracted to boll weevil infested squares; and showed no response to uninfested squares. Females did not respond to volatile compounds (copaene, caryophyllene, humulene, or caryophyllene oxide) isolated from cotton squares; but these females were significantly attracted to boll weevil frass. The females showed 3 typical behavioral responses to infested squares or weevil frass, 1) Direct flight to the attractive material; 2) Flight to the vicinity of the attractive material and then jumping directly to the attractive material; and 3) Flight to the vicinity of the attractive material, and direct walk to the sample. Number 3 was the most common behavior used to localized the sample. The searching and finding processes were not random and in all cases, females appeared to be able to readily locate their host.