Gas Tank Vent

I was in my trunk and noticed that the small 1/4" vent tube that connects to the fill tube was laying open in the trunk. My question is does this metal line run thru the filler to trunk seal and just rides like that, or is it suppose to return inside the tank? Now I know why when I would fill the car up that the gas fumes were so bad. Thanks for any and all help. Oh by the way this is on a 69 Dart.