Lunar Periodicity
This extract was created in the absence of an abstract.
Excerpt
A biological rhythm may be defined as lunar periodicity if the maxima and minima of the rhythmical process appear once or twice in every lunar month at the same time, that is, at the time of a certain moon-phase, or, in other words, if they follow each other periodically in distances of about 30 (precisely 29.53) or 15 (precisely 14.77) days.
Up to now many cases have been found in field studies, as well by occasional observations as by statistical treatment of repeated observations. Many lunar periodic processes are connected with reproduction. Some examples may be given here: In the Pacific and the Atlantic Palolo-worm (Eunice viridis and E. fucata) the mature epitoc parts swarm, according to observations of many years, almost exclusively during a few nights while the moon is in its last quarter [1, 2]. In the Chironomid Clunio marinus hatching of the imago takes place only within...
