THE LONG HAIRED ALBINO BABES OF BARNUM'S BIZARRE BAZAAR -- Florence and Mary Martin
The sisters Florence and Mary Martin were "employees" of P.T. Barnum of New York during the 1800s.
6 months after posting this image, Flickr commenter Lyneille made positive ID.
A thumbnail of these two is found here : www.sideshowworld.com/BL-History-Albinos.html
A web search will turn up more info.
Thanks, Lyneille !