Cephalopods

http://www.tonmo.com/science/fossils/nautiloids.php

http://www.nhm.ac.uk/hosted_sites/tcp/index.html#intro

http://www.ammonoid.com/

http://en.wikipedia.org/wiki/Cephalopod

http://www.cephbase.utmb.edu/imgdb/imgdb.cfm

http://www.oum.ox.ac.uk/thezone/fossils/inverts/cephalo.htm

Cephalopods- Cadaceras

http://www.fossilmall.com/EDCOPE_Enterprises/ammonites/AA036/AA036.htm