What kind of green snake are you talking about? Rough, Smooth or Red Tail Rat Snake? I'm guessing a Rough, they are insectivores and are hard to keep, very specific requiremnets. As for mixing them with lizards, I see it all the time but advise against it.
Finally someone that gives a little thought towards the comfort of their snake. Most experienced keepers say the tank should be nearly long enough for the snake to stretch it's whole body out. Also, I didn't mean a 14 inch straight line measurement, I meant if you wrapped a piece of 14 inch string around it's thickest point the ends would be close to touching. I'm just speaking from personal experience here. Would hate to see a full grown ball python in a cage that small. Such a waste of a beautiful snake...
