[Wikipedia] Range, Similarity to F. pinetorum: Fritillaria atropurpurea is a species of fritillary known by several common names, including spotted fritillary, purple fritillary, spotted mountainbells, spotted missionbells, and leopard lily. Distribution Fritillaria atropurpurea is native to the Western United States, where it is often found beneath trees in moldy leaf litter at elevations of 1000 to 3200 m. This species has the widest distribution of fritillaries in North America, growing from California, Arizona and New Mexico north to Oregon and North Dakota. This species is similar to Fritillaria pinetorum, but it has nodding flowers compared with the latter's erect blooms. (link added by Mary Ann Machi)