I thought it was coming out of the carb, but now that I took it apart, it looks like it cam from a hose that is in the crankcase.
That hose is the crank case breather vent. It will move some oil out with air being blown from the crank case if there is a bit too much oil in the engine. If it doesn't purge excess oil in short order, you can take a couple oz. out. Check the oil level if you do adjust it. You don't want it to be too low.