a) Alien: HR Giger's Egg silo interior version II (work 388) 1978
b) References The Oysters with the Walrus and the Carpenter' for Lewis Carroll's Alice Through The Looking Glass (published 1871) by John Tenniel?
First thing to note is the idea would be that the oysters became the egg shaped spores,
but Giger wasn't putting them anywhere that would conform to the
c) It would appear as if the apron of the carpenter became a starting point for one line of ribs going upwards and the right side of the stone he was sitting on became the divider on the right
d) Giger's painting lacks any bulbous form that might be a trace of the walrus but I'm drawn to think that the spinal columns along the wall might be related to the idea of his tusks