Abstract
SUMMARY The ability of a range of carbohydrates to support the growth of plasmodia of the myxomycete Physarum polycephalum was investigated and a method for the objective study of the chemotaxis of plasmodia was developed. Plasmodia showed positive chemotaxis to solutions of glucose, maltose, mannose and peptone, and to galactose after a delay. They did not respond to sucrose, fruc- tose or ribose. The chemotactic effectiveness of sugars paralleled their ability to support growth.