That's.... not a caterpillar. That's the larvae/maggot of the common cockchafer, as far as I can tell. Otherwise known as Maybug.

The black egg is century egg, a duck or chicken egg preserved in an alkaline solution (usually quicklime, ash, salt and rice hulls). It's not horrible in the way, say, surströmming is, but it an unusual taste and texture that makes most people balk at the idea. Honestly, I'd pick it over even the onion.

The black egg is a preserved, maybe duck, egg, and they are quite yummy.

The egg is a century egg/tea egg and common in a few Asian cuisines. It’s awesome in rice porridge.

i've had the caterpillar dried and seasoned. underneath the seasoning it had a nutty flavor.