Thirteen examples of virus or viruslike related pathoses in non-insect invertebrates are described. From consideration of these examples, it becomes obvious that detailed descriptions of pathogenesis of virus diseases in non-insect invertebrates has not kept pace with the frequency of new reports of viruses from these invertebrates. When possible, it is of utmost importance for authors reporting viral entities from invertebrates to include as much information as can be collected on the disease syndrome, cellular pathogenesis, physiological and behavioral effects and tissue distribution of the virus. In some cases, information has been so scant that readers are not even certain as to the prevalence of the virus in reported hosts. Basic information on the nature of non-insect invertebrate virus diseases is needed for several reasons. Insights into mechanisms of pathogenesis and pathogenic effects in invertebrate viruses may give better understanding of vertebrate virus diseases. Further, a major opportunity exists with invertebrate virus disease to investigate the fundamental aspects of cellular immunity.