So much has been written lately about the artificial production of aortic lesions in rabbits by intravenous injections of adrenalin, nicotin and other substances, and their relation to the lesions in human arterial disease, that it would seem of interest to record a case of spontaneous atheroma accidentally observed in a rabbit. The rabbit in question was a large, healthy, well-developed female, raised in the country, which had just been received by the laboratory and had not been at the college over eight days. It died of acute anemia in the course of an unsuccessful surgical operation. Examination of the aorta showed a normal caliber and normal elasticity of the wall. In the arch near its beginning there were several light yellow, fairly well circumscribed, slightly raised, oblong spots from 2 to 3 mm. in greatest diameter, which attracted attention on account of their great similarity to the initial stages