Country queries

QI was removing self-set potatoes from a compost heap and these rolled out. At first I thought they were a form of fungi but, on close inspection, I could see this worm-like shape partially out of one of them. I couldn’t save this one but put the others back in the compost. What are they and will the others survive?

MC, by email

AThese are grass snake eggs. Grass snakes mate in April/may and the females lay their eggs in June/july, often in compost heaps as the heat in them helps to incubate the eggs. The eggs can take six to 10 weeks to hatch, depending on the temperature. With luck, the eggs should survive if returned to their warm nesting place immediately. Once the young snakes have hatched they have to fend for themselves.