Inhibition of Nematocyst Discharge correlated with Feeding in a Sea Anemone, Calliactis tricolor (Leseur)

Abstract

IN spite of much work¹ neither the mechanism nor the nature of control of the discharge of nematocysts is well understood. These stinging capsules, characteristic of coelenterates, have generally been assumed to be independent effectors^2,3, their discharge depending solely on external stimuli, with the animal exerting no control. Some coelenterates, however, seem to be able to modify nematocyst discharge^4–8, and we feel that nematocysts should therefore not be considered true independent effectors. Working with the Florida sea anemone, Calliactis tricolor, we have observed a sharp decrease in the number of nematocysts discharged with increased feeding.