Observations on Aphid Cornicle Secretions

Abstract

Physiological and chemical observations were made on the cornicle secretions of Myzus persicae (Sulzer), Acyrthosiphon pisum (Harris), and a Chaitophorus sp. If appropriately stimulated, a droplet of fluid, about 150µ in diameter, appeared at the tip of the cornicles; this droplet hardened in about 20 seconds. Chemically, the hardened droplets were composed primarily of triglycerides. Myristic acid was the major fatty acid moiety of the trigly-cerides.