Many Native people have surnames that are two words combined. In some cases, how to index or categorize these names is obvious based on how the name is written. For example, we have two people with the surname Blackhawk and in both cases the name is written as one word. So there is no question as to whether the surname begin with Black or Hawk.
Not so clear is Adam Black Fox. In the WWI draft registrations, he is indexed under Fox, meaning that Black is assumed to be a middle name. But having worked with Native names, I recognized that his Native name is more likely Black Fox, used as one “name” if not written as one word. Looking at the actual record itself, Adam signs his name Adam Black-Fox. In questionable situations, I always look at how the registrant signed his name. How they sign their name and how the registrar records the name at the top of the same card is not always identical.
In the Native Heritage project, these names are indexed using the Native approach. In this case, Black was clearly not a middle name, although it could have been. He is recorded under B, for Black-Fox.