Some New Techniques for the Preparation and Illustration of Polycystina (Radiolaria)

Scanning electron microscopy (SEM) and light-microscopy photographs of the same radiolarian specimens are vital for thorough and complete descriptions of polycystine species. Several media for light photography have been tested, including stained and unstained aqueous solutions, oils of varying refractive index and Farrants' medium. The latter proved to yield excellent results; it can be used for permanent preparations, and also allows for an easy and fast retrieval of the skeletons for ulterior SEM photography. Paired SEM pictures of radiolarian tests for stereoscopic viewing can furnish much useful information unavailable by other means. A detailed scheme on the steps to be taken for the preparation of Polycystina-containing samples is included.