On four occasions a naturally occurring mouse leukemia, which was maintained by serial passage in weanlings of the Princeton strain, was superseded by a syndrome typical of acute hepatitis. Once initiated, the disease was regularly transmissible by the injection of liver suspensions of sick mice. It was also passed, though irregularly, by feeding such suspensions, and it also followed cannibalism.
The course of the disease after intraperitoneal injection of liver suspensions into normal weanlings was commonly less than 7 days and the mortality rate nearly 100 per cent.
Focal or diffuse necrosis of the liver was the only constant lesion at autopsy. On recovery, which occurred only in exceptional cases, cirrhosis was often found.
The primary source of the disease was undetermined. Latent carriage by healthy mice was not detectable on direct examination nor by the serial passage of suspensions of normal livers.