Mystery Part - TR6/250 Engine

[JoeSimcoe@aol.com]

I am dismantling my TR250 and have a mystery I can't figure out.  On the Oil
Sump - there is a hose that hooks into it on the carburator side - fairly
large diameter, probalby 1/2" - it was not hooked up to anything at the other
end when I got the car, and I can find no mention of it in any of my manuals.
 

It looks like a breather hose, or maybe a return from the cylinder head? ? ?
?? 

Does anyone have any idea what this could be? ?

TIA
JoeSimcoe