rather like a big paper clip. Many of the earlier heteromorph forms had regularly coiled shells barely distinguishable from the homomorph ammonites (for example, the Lower Cretaceous genus Deshayesites). Some offshoots of the uncoiled varieties even went back to being regularly coiled. Most notable among these were the Scaphites, Hoploscaphites and their relatives, which were mostly regular spirals in shape except for a very slight hook at the end. The Late Cretaceous enjoyed the widest variety of heteromorphs, including the straight-shelled Baculites and Sciponoceras; the helically coiled Turrilites; and the bizarre Nipponites, which looked more like a ball of string than anything else. Some forms combined different coiling modes. For example, Nostoceras started off with a helix like a Turrilites, but had a planar hook hanging underneath, more like an Ancyloceras. The thin shelled heteromorphic ammonites probably lived at depths . Classification Suborder Ancyloceratina Superfamily Ancyloceratoidea Family Acrioceratidae Family Ancyloceratidae Family Bochianitidae Family Crioceratitidae Family Hamulinidae Family Hemihoplitidae Family Heteroceratidae Family Himantoceratidae Family Labeceratidae Family Macroscaphitidae Family Ptychoceratidae Superfamily Deshayesitoidea Family Deshayesitidae Family Parahoplitidae Superfamily Douvilleiceratoidea Family Astiericeratidae Family Douvilleiceratidae Family Trochleiceratidae Superfamily Scaphitoidea Family Scaphitidae Superfamily Turrilitoidea Family Anisoceratidae Family Baculitidae Family Diplomoceratidae Family Hamitidae Family Nostoceratidae Family Turrilitidae Footnotes References Pasch, A. D., K. C. May. 2001. Taphonomy and paleoenvironment of hadrosaur (Dinosauria) from the Matanuska Formation (Turonian) in South-Central Alaska. In: Mesozoic Vertebrate Life. Ed.s Tanke, D. H., Carpenter, K., Skrepnick, M. W. Indiana University Press. Pages 219–236. External links Scientific report on the functional morphology of Cretaceous heteromorph ammonites Ammonitida suborders Prehistoric animal suborders Mollusc suborders Late Jurassic first appearances Maastrichtian extinctions