That could very well be, Stefan... Especially since "Das Meerhäschen" didn't appear until the later editions of the collection.

'Rumpelstielzchen' isn't exactly a good comparison, though, as we are told what kind of creature he is (or at least, what he looks like): a little human being. And besides, Rumpelstielzchen is a proper name. I'd be equally frustrated trying to figure out what kind of beast you are if I tried looking up "Stefan Wirz" in my Natural History field guide...

Off to reread that web page posted by Mudguard... maybe Google will have a clearer translation than babel fish.