Apparent mitogenetic inactivity of active cells

Abstract

A photo-electric counter of the Geiger-Muller type, sensitive to 50 quanta per cm.2 per sec. at 2500 A., failed to detect the emission of radiant energy (varying in wave-length from 1800 to 2800 A.) from the fertilized eggs of sea-urchins at any phase of their mitotic cycle. No radiation was observed from cultures of active spermatozoa, or of growing yeast. Misleading results can be obtained if water vapor or other volatile material is allowed to condense on the surface of the counter.