I found something on the fish at
http://bookshelf.info/wordlists/e/eec/www/...=I.html#ichthus
ichthus
An icon in the shape of a fish that many people display on the trunks of their cars or in their doorways. For years until I learned its proper name I called it a Jesus fish. One reader tells me people in his area call it a holy mackerel. The fish is usually filled in with Greek letters interpreted as an acrostic, meaning ``Jesus Christ Son of God Savior''. It was originally a pagan symbol of fertility.