Peaked fenders and swirly chainring. I'm gonna put my dollar on Roadmaster, though I wouldn't be surprised if it were a Murray or a Huffy. The front fender looks to be on backwards but that's sort of a matter of taste. The fenders are worth a little bit, too.
I think that's an oil port but open it up and look. If it's a port squirt a syringe full of automatic transmission fluid (or motor oil or anything other than 3-n-1 or WD 40) down there.
remember that 26x1.75" tires won't fit 26x1 3/4" rims and have fun.