Mary, I have a very similar problem from roughly the same era. My great-grandmother is said to have been Native American and adopted, but thus far she is listed as "white" in all the censes. She was born in 1861 (and it's pretty clear in her picture that she is not white). - Ava
Yes, we are going by photos of family members and legends. Nothing documentary.
A relative told me her obit from the 1950s listed her birth name (at least her first name), so I'm hopeful they can locate that again. If not, I'll look for newspaper archives the next time in the area. If you are interested in the subject of Maine Indians generally, there is a book titled "Unsettled Past, Unsettled Future: The Story of Maine Indians by Neil Rolde (2004) which is informative (generally speaking).