The woman is the portrait detail above is Rebecca H. (Harbert?) Whelan (1877? - 1950?), about whom little seems to be known, if Googling the Internet is any indication. It seems that her father (can't get a Google hit on him, either) was a trustee of the Pennsylvania Academy of the Fine Arts, where the painter, Thomas Pollock Anshutz (1851-1912) taught. Here is the entire painting:
The painting can be seen at New York's Metropolitan Museum of Art, and the museum's Web page devoted to the painting is here.
I wrote about Anshutz here, wondering if the woman who posed for "The Rose" was the same one depicted in "The Incense Burner." It turns out she was the same model. Moreover, Anshutz portrayed her more than twice.
Below are paintings by Anshutz where Rebecca was either definitely the model or quite possibly was.
From about the same time as "The Rose."
This is the largest image I could find of this painting. Rebecca is known to be the model.
I'm not sure if this is Rebecca. The complexion is too ruddy compared to other Anshutz depictions, but the hair, nose and eyebrows suggest it might be her.
Another "maybe" portrait. This is the largest image I could locate while assembling this post: a larger one might offer a closer look at the nose which then could be compared to the profile in "Tanagra." The nose seems somewhat like Rebecca's and ditto the eyebrows and chin, though the position of the head makes comparisons difficult.