I remember a very old short story/novella about a man on Mars who finds a creature who lays pyramid shaped eggs, the eggs hatch and a new creature lays an egg and so on. Think the man is a stranded astronaut but can really remember what the purpose of being on Mars or anything else the creature does. Had 50's sort of feel to it but not sure.
This is Stanley G Weinbaum's "A Martian Odyssey".
There was a line of little pyramids - tiny ones, not more than six inches high, stretching across Xanthus as far as I could see.
Also the answer to this old question: Story about a man and an alien exploring an alien world