The Responses of Heteroxenia (Alcyonaria) to Stimulation and to Some Inorganic Ions

Abstract

1. In Heteroxenia there are two distinct kinds of response; one is the unco-ordinated rhythm of the autozooids; the other is the maintained spasm which is co-ordinated over the colony. 2. The absolute refractory period of the conducting system which co-ordinates the spasm of the colony is found to be 0.08 sec. 3. The actions of excesses of potassium, sodium, calcium and magnesium ions suggest that the rhythm resembles that of Scyphozoa. 4. The organization and overlap of the two conducting systems in the autozooid disk recall the scyphozoan pattern of two nerve nets. However, in Heteroxenia there is little evidence of interaction between the two systems.