Hi, those are cavity drain holes to keep water from pooling inside the housing and freezing in the winter.
What does the effluent smell like? Is it gassy/oily? Or does it stink like sulfur? If the latter, that's gear oil leaking from the gearcase. If the former, it's likely just oily discharge from the engine itself. Especially if it's darker in color. A grey "milkshake" discharge could mean water and fuel mixing in the combustion chamber due to a leak (such as leaking exhaust manifold or head gasket), but a small amount is normal, as any unburned fuel/oil mixture is gonna go out there.
If the engine is running well and the spark plugs look normal (not too sooty, not so clean that they look like they were steam cleaned), and there's no water coming out of the gearcase when you pull the drain plug, probably normal.
Now, if it stinks or if you have water coming out of the drain plug or a "milkshake" in the gear oil, you've probably got a leaky oil seal.
The most common place for leakage is the driveshaft oil seal under the water pump assembly. To repair that you'd have to pull the lower unit and remove the pump housing, impeller, and lower plate. The oil seal resides beneath. IIRC the 55hp driveshaft comes right out and you can pry out the old seal and drive-in a new one.
Anyway, that should cover all bases, let us know what you find............ed