I'd been wondering whether a date in the 1860s might be a little too early. The lad looks to me possibly around 14-15, which would push it into the early 1870s. But there might be other things that would help with the dating.
Shamrockgirl - is there anything else you can tell us about the photo itself, or if possible show us in a scan? eg: size, mount, anything printed on the back, anything indicating the photographic process used? These things can help enormously with dating, but please don't damage it if this kind of thing isn't immediately obvious.
The other thing is that the image you posted looked to be in greyscale, and the deep contrast meant that there's little or no detail to be seen in the darker areas. Would it be possible for you to scan it again with less contrast? Full colour mode might also help to bring out extra details.
Someone mentioned what looks like a foot sticking out from the lady's dress, and I'm wondering if that might be clearer with another scan. In the early days of photography exposures were very long, and it was common to use various stands, supports etc to help people keep still, so could this be part of one of those?
