Regulation der Cilienmetachronie bei der “Fluchtreaktion” von Paramecium*

SYNOPSIS. Paramecia induced to perform high rates of avoiding reactions by mechanical stimulation and the action of Ba ions were instantaneously fixed with OsO₄. Quantitative evaluation of the preparations revealed, among other things, metachronal stages of the transition between the ciliary patterns of swimming backward and forward. In each of the transitory stages, metachronal waves of swimming forward were found at the anterior end and waves of swimming backward at the posterior end of the animal. This confirms the so-called Párducz-scheme of avoiding reaction for the case of homogeneous chemical stimulation as well as for mechanical stimulation.