In fact, animals like jellyfish and worms are lungs all over.
It is of interest to consider a common animal like the jellyfish Aurelia.
Normally a jellyfish has its parts in four or multiples of four.
He was using the jellyfish as an example of a life form all but invisible.
Just like jellyfish, they will not stand any rough handling.
Its eyes were jellyfish, its hair ...