Back is blank.
I have no idea who this lovely lady is, so I'm working with what the little I've got.
Although the bottom of the words are cut off, I think I can see Swain and Yarmouth there. Sure enough, L.G. Swain was a photographer newly set up in Yarnmouth, Nova Scotia, according to Hutchinson's Nova Scotia Directory 1866-7. Mr. Swain is still there in the 1870-1 McAlpine's directory and the 1881 census, although I don't see him in 1891.
Ad for L.G. Swain in 1866-7 directory.
Photo Detective had a photo up recently that shows similar frizzy bangs, slimly-shaped long bodice, long line of buttons, and slim arms. That picture is from the early 1880's and I'm thinking this one might be too. And check out all these 1880's hairstyles! Fits right in, don't you think?
This stuff is fascinating, honestly.