Such a lovely orange lily drawing. It is the work of Margaret Armstrong (1867-1944). It was one of many lovely flower illustrations that appeared in her book Field Book of Western Wild Flowers.
Armstrong called these lovely blooms Orange Mariposa Tulip. They are a desert flower found in area from Southern California to Arizona and Mexico. It can have vermilion, orange or yellow flowers on short stems. The scientific name of these lovely orange lilys is Calochortus Kennedyi. Mariposa is a Spanish word which means butterfly. The pretty drape of the petals do make these flowers look a bit like butterflies.
These wildflowers tend to thrive in areas where wildfires had previously burned. They can be found in some gardens but they are quite particular about their environment and some report they are difficult to get to rebloom.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.