Cocculolidine isolated from leaves of Cocculus trilobus DC. (Kamiebi in Japanese), the host plant of Japanese fruit-piercing moths, exhibited insecticidal activity to leaf hoppers (Nephotettix bipunctatus cincticepts Uhler) and Azuki-been weevils (Callosobruchus chinensis Linne), however it had no activity to larvae of the fruit-piercing moth, Oraesia excavata Butler (Akaeguriba in Japanese), suggesting an interesting phenomenon of the host-parasite interrelationship. © 1967 Taylor and Francis Group LLC.