fold
From ZooTerms (Dictionary of Invertebrate Zoology)
Revision as of 23:40, 13 September 2013 by Andreas Plank (Talk | contribs)
fold (noun; Anglo-Saxon folde, a fold): 1. A doubling or folding.
2. (Brachiopoda) A major external elevation of the valve surface, convex in transverse profile and radial from the umbo.
3. a. (Mollusca: Bivalvia) A broad undulation in the shell surface which is directed radially or comarginally. b. (Mollusca: Gastropoda) The spirally wound ridge on the interior of a shell wall
See also: columellar fold, parietal fold.
