I've never seen a shirt/jacket lke that before, but then again Confederate uniforms aren't really my specialty. That color placket on the front is interesting. If you blow the photo up, it looks like the jacket might end right at the bottom of the sash, perhaps. But it's hard to tell - the jacket might continue into the indistinct bottom of the portrait. So, I'm not convinced it's a battleshirt because the collar doesn't look like other battleshirts I've seen, but I can't definitively make it into a short coat, either. A couple other cool details, though: I think he's wearing a Federal forage cap, a pretty common Confederate practice. His belt buckle is probably the Federal officer's eagle buckle, worn on an officer belt; I think you can see the lines of stitching on the belt. He's wearing the sash worn from Lt. through Col., and 2nd LT shoulder straps, both of which have been hand-colorized (a pretty common period technique). The pistols on his belt are Smith & Wesson #2s, .32 caliber. Although they were woefully underpowered little peashooters, they were the only metallic cartridge pistols available in 1861 and were very popular (Custer owned a pair). They were sold in boxed matching sets. He has them in correct fitted holsters on his belt, not tucked into the sash or belt. I think they're his own pistols. Infantry officers, contrary to reenactor practice, often carried small caliber handguns as a side-arm. They knew they were there to tell other people to shoot and if they have to do it, something has gone dreadfully wrong. His pistols would be consistent with the rank and sash, so I think you've got an early war Confederate infantry officer there, possibly militia but necessarily.