This small textbook is written from the point of view of a general biological approach to viruses. This approach is similar to the one that considers bacteriology as a biological science. The material is presented from the point of view of the geneticist, plant physiologist, or biochemist, rather than that of a practitioner of medicine. No viral diseases as such are described. The central concept is of viruses as operating constituents of functional cells. In this respect the virus lives the life of the host. At the same time, viruses are inert particles that have been extensively studied by physicochemical methods in their purified state. Indeed, when they are highly purified and crystallized they seem to bridge a gap between inanimate and living things.
Various chapters deal with the detection and identification, measurement of size, and chemical composition of viruses. The reaction of viruses with their plant and animal hosts,