The viruses of the family Rhabdoviridae have an exceedingly broad host range and are widely distributed throughout the animal and plant king- doms. Animal rhabdoviruses infect and often cause disease in insects, fish, and mammals, including man. The prototype rhabdovirus, vesicular stomatitis virus VSV), has been extensively studied and provides perhaps the best model system for studying negative-strand viruses. The popularity of VSV as a model system...