I would agree with Pottsy - the pipe #38 is on the carb side (after the air filter), which means the crankcase is venting back into the engine -essentially keeping those nasty fumes that Californians particularly hate, away from the atmosphere, while pipe #38 collects any excess oil... (I'm presuming the pipe is clear so you can see if it is filling up, and then drain it? - it is on my new Tenere anyway...)
Pipe #40 is similar to those found on virtually all dirtbike airboxes, and is simply for emptying out any water and crud that might have found it's way into the top of the airbox (before the air filter)... as Pottsy says, you don't really want oil on that side of the air filter (if only for environmental reasons) - although a number of dirt bikes do vent the crankcase into the pre-airfilter side as their airbox is simpler in design, and their air filters tend to be cleaned a lot more regularly anyway...
xxx
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