Maybe a potter wasp?

http://farm3.static.flickr.com/2356/2510560027_7c9d0dc2b1.jpg?v=0

A paralysed caterpillar is stuffed in through the hole, & injected with a wasp egg & sealed. It then hatches & eats the prey alive...
Some of these wasps are huge, but rare. I saw one in the Charante Maritime a couple of years back, it was at least 2" long!

Last edited by Alan Belson; 09/16/09 07:28 PM. Reason: clarify
Wood work but can't!