the existence of coal bed in antartica indicates that the continent once had what?

There is evidence that Antarctica was once a lush and tropical island.

scientists have found FRUIT TREES under all the ice.........which indicates the climate on the land mass once supported  that sort of vegetation and pollenisation required to  grow fruit trees,  so clearly the land mass once supported such life. 

A forest, and a more pleasant climate

Lots of vegetation, probably as a hot steamy jungle. 

Lits of vegetation at one time and much warmer temperatures and that Antarctica has moved A LOT.

Swampy Forests !