Examination of Fossil Coccoliths in the Electron Microscope

Abstract

RECENTLY, the use of the electron microscope in investigating the form of fossil coccoliths has been reported by Deflandre and Fert¹, and a preliminary revision of the taxonomy has been given by Braarud, Deflandre, Halldal and Kamptner². The published electron micrographs show little more than the outline of the coccoliths and must be supplemented by examination at lower magnifications with the optical microscope. This unsatisfactory situation is due to the coccoliths being opaque to the electron beam. The difficulty has been overcome by examining shadowed replicas of the coccoliths, which give excellent information about the relief as well as the outline of the coccoliths. The accompanying illustrations compare a shadowed replica (Fig. 1) with a similar coccolith photographed in the transmitted beam (Fig. 2).