Backing a hunch, I made a short search on the internet and came to the conclusion that Emily Stokes was the photographer. I noticed that her address was in one case extended by the inclusion of 'Pelham Studios', which probably clinches it.

Thanks, Limbo! I think I was thrown off by the handwriting rather than a printed name and address.
Happy to hear of any woman photographers from back then.
Curious to see if I can find out more about her.

Found online - taken from the following book:
Willard, Frances Elizabeth. Occupations for women: a book of practical suggestions for the material advancement, the mental and physical development, and the moral and spiritual uplift of women.Cooper Union, N.Y.: The Success Co., 1897.

Mrs. Emily Stokes of Boston, is an example of what a woman may accomplish in photography. When compelled by misfortune to give up her London home, she came to America to begin life among strangers. Having been associated with enthusiastic photographers in England, and believing that the position could be filled by women as well as men, she resolved to enter the field as a professional. For sixteen years she has aimed to produce the true child portrait. She has conquered difficulties, and is an enthusiastic and successful artist. "This one thing I know," she said brightly, and it would be well if many girls could say the same. "I know every detail of the work; it is the only way to success," she added, as she glanced about the room at the pictures of sweet child faces.

So interesting where these photographs lead us. The history of Emily Stokes is inspiring, as is Ms. Willard's efforts to assist women in finding rewarding careers.
Also, in trying to reply to your comment about the "aging hippie" photo of my dad in costume, I somehow completely erased the photo from Ipernity. I know he would have had a good laugh at your comment.

Maybe it's not us, Rick. I was writing a reply to Laura (raingirl) and her comment disappeared. I was puzzled but assumed it was my fault somehow.
Hearing you say the same, makes me wonder...
I didn't realize that was your Dad but I have a faint memory of seeing it before, so perhaps I did know at some point!

That dress is quite unique, and the info about Emily Stokes is quite interesting. Stokes also took a well-known photo of Helen Keller and her dog (see 100 Years Ago: Social Gatherings on the Photographs, Pistols & Parasols: Celebrating Early Women Artisan Photographers blog).

The influence of Julia Margaret Cameron's portraits is still felt today. Not only did she master what was then new technology (less than 25 years since photography was invented) but also defined a style and stuck to it despite narrow-minded criticism. Julia Margaret Cameron was self-assured and adventurous, a heroine of her age. But her path was made possible by wealth and social connections at the highest level. It wasn't enough for a woman simply to be a genius, and it probably still isn't even in nations and societies which might claim it is.