Mystery of the Swiss Cheese Leaves

In recent weeks, we've been noticing more and more leaves around the garden that look as though someone's been going around hole-punching them. And while seeing punctured foliage usually elicits a sense of concern about pests and disease, something about the smooth, skillfully-crafted shape of these holes makes them seem benign to me... artful even!

  Mystery of the Alien-Pod

A couple of weeks ago, Seán found a mysterious, silvery pod on the ground beside the house, about the size of a lime. It appeared to have been there for a while, as it was very light and seemed dried out. We took our guesses: was it a plant-pod? Some kind of egg sac? I thought it might be an owl-pellet, due to it's hairy outside texture, shape and size. We decided to lovingly refer to it as the “alien pod”:

There was only one thing to do in order to solve the mystery – cut it open: