A COMPARISON OF FIVE EFFECTS OF ULTRAVIOLET LIGHT ON THE ARBACIA EGG

Abstract
The demonstration of 5 different effects of u.-v. radiation on the egg of Arbacia punctulata indicates that more than 1 basic photochemical process goes on there. Photorecovery is observed in only 1 of these. The need for caution in interpreting such effects is obvious. Evidence for a different mechanism for the timing of cleavage in eggs activated by u.-v. radiation as compared to normally fertilized eggs is presented. The bearing of these studies on survival curves for microorganisms is discussed.