The name James is a girl's name of Hebrew origin meaning "supplanter". James and is often added to lists like Middle Names for Girls and discussed in our forums with posts like "Adding then Eliminating - Boys Themed".
From the experts:
James for a girl? Well, why not? This is one of the boy names for girls" gaining a lot of attention these days -- it's already been used as a pet name for some Jamies. Now that Blake Lively and Ryan Reynolds have chosen the name for their daughter, chances are that we'll be meeting more girls named James than ever before.
The only real argument against using James for your daughter is that it's been so widely used for so long for boys, and is more fashionable today than it's been for a couple of decades. Do you want people to do a double-take every time they hear your little girl's name? If so, James might be the choice for you, but if not, keep looking.