carburetor overflow hose?

[lukasbasic]

after taking off and putting on the back tire, i noticed a tube which is hanging down by the air filter, which doesn't plug into anything. i'm worried that i detached it from somewhere, but i can't find any place where it would fit. the scooter runs.
see attached picture. i went through the service manual but it is hard to see if its this one

i marked the tube in yellow.
see url
http://tinypic.com/view.php?pic=11r3qtx&s=5#.Ul3E91A_vZY

[PeTroL42]

That's the fuel drain hose for the float bowl.

If you look on the other side of the carb, the hose should be attached to a nipple that has a flathead screw on it.  If you turn the screw, the fuel will drain out of the float bowl and down that hose.