Ok Gary and C.H. really appreciate the replies on this tank. I did some more research and found out that it originally was one of two tanks that were attached to the bottom of a Buddy L transport plane. Most of the original tanks were lost and I'm sure kids played with them and they were the first things lost. I included a few pics of a plane that I found with the tanks mounted to it.
Thanks for the pics on the critter tank have bought a sold a few of those over the years as well as multiple other styles of marx tank. When I first got it I just had banked on the fact that it was marx but wrong was I!! Thanks again on the replies and hopefully if nothing else it helps out others with this same style tank lying around.
JEFF