Intranuclear inclusion bodies, typical of the developmental stages of herpesvirus inclusions, were observed in cells of the liver, spleen, bone marrow, and small intestine from a prairie falcon (Falco mexicanus). Inoculations of a suspension of liver tissue produced lesions on the chorioallantoic membranes of 12-day old chicken embryos. Three sparrow hawks (Falco sparverius) were fatally infected by intramuscular or crop inoculations of suspensions of prairie falcon liver or chorioallantoic membrane.