The Collaborative International Dictionary of English v.0.48:
Conchology \Con*chol"o*gy\, n. [Conch + -logy.] (Zool.) The science of Mollusca, and of the shells which they form; malacology. [1913 Webster]WordNet (r) 3.0 (2006):
conchology n 1: the collection and study of mollusc shells [syn: conchology, shell collecting]