How old are those forms ?
"...leafs are small" - yes. Very. 300-1000 metres long.
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No question about that, whether jelly animals exist or not. People have been blind to those, and don't ever think, what rock really is. Rock, very often, is pile / layers of dead animals. When humans' time will end, we'll be there. In stones.
Jelly animals in the first times on a planet are kilometres long, thick and thin leaf-resembling things with a crabbing-end-nature (crabbing root), They can co-operate as building common walls, share root, maybe touch each other closely in a beneficial way but stay separate, build together vein-systems and big, complicated-looking machine looking systems of size of kilometres, ... <-- land could tell that
Kiutaköngäs