The Tombstone of Dead Leaves
The 999 arrives at a hollow planet with no gravity; as a result everything is a lot fatter looking, and can float through the air. Tetsuro and Maetel are confronted by cattle keepers but are able to escape. As they travel to their next planet Tetsuro meets an artist who has a wooden machine body. When they travel through a planet full of leaves, an electric mushroom threatens to destroy the train.
Aired 01/02/1979EP 21 - The Tombstone of Dead Leaves

Galaxy Express 999
After witnessing the death of his mother and being left for dead at the hands of Count Mecha, ten-year old Tetsuro Hoshino is awakened by a mysterious woman, Maetal. In exchange for only his company, Maetal offers him the ride of his life on the Galaxy Express 999. It is said that those who travel aboard the legendary train to the end of the line can receive a free mechanical body and with it, immortality.
Impoverished and alone, Tetsuro leaps at the opportunity and joins Maetal on a quest that will span the cosmos. As the Galaxy Express 999 makes its way across our solar system and beyond, Tetsuro is drawn deeper into a dangerous universe where peril lurks at every stop.
(Source: Discotek)