The unidentified woman was probably wearing her best dress when she posed for photographer "Tyler" of Boston. http://forgottenfacesandlongagoplaces.blogspot.com/2013/05/fashionable-friday-civil-war-era-boston.html
CDV Photo Lovely Woman Seated in Large Hoop Dress Tax Stamp Civil War Era Reading PA | eBay
Forgotten Faces and Long Ago Places: Fashionable Friday - Civil War Era Couple - Early 1860's
The woman in this photo is wearing a Swiss Belt. This belt was cut wide with a triangular piece in front. This was a popular accessory of the Crinoline era.
How women dressed in the 1850s, possibly pregnant
1860's - I think I can see a little veil on the hat.
1861 Day dress from Godey's magazine. This is one of those dresses which I think qualifies as belonging on their ACW era runway. I don't see this as a common fashion.
Civil War lady. Love the ruffles on her dress! The pattern I'm using looks like this dress.
Charming young miss in fashionable skirt, jacket and fine waist combination with decorated hat.
The Barrington House Civil War Era