THE STRUCTURE OF INSECT VIRUS PARTICLES

Abstract

Viruses from 4 types of insect virus diseases were examined on the electron microscope by means of ultrathin sections. These are nuclear and cytopiasmic polyhedral diseases, granular diseases, and virus diseases without intracellular inclusions. Sections reveal that there is a intimate membrane enclosing the substance of the virus particle. In the polyhedral and granular diseases there is also an outer capsule which is itself enclosed in a polyhedral crystal or in a granule. In some of the cytopiasmic polyhedral viruses the particle is composite consisting of 5 or 6 sub-particles. Sections through one of the viruses, from the diseases without intercellular inclusions, show some of the particles to consist of apparently empty shells.