1) Mollusc shell
Found on
https://www.crosswordclues.com/clue/prodissoconch
A prodissoconch (meaning first or earliest or original shell) is an embryonic or larval shell which is present in the larva of a bivalve mollusk (clams, scallops, oysters, etc). (The homologous structure in gastropods (snails) is called the protoconch.) The prodissoconch is often but not always smooth, and has no growth lines. It is sometimes stil...
Found on
http://en.wikipedia.org/wiki/Prodissoconch
No exact match found.
