The Collaborative International Dictionary
malacostracology
Carcinology \Car`ci*nol"o*gy\ (k[aum]r`s[i^]*n[o^]l"[-o]*j[y^]), n. [Gr. karki`nos a crab + -logy.] (Zo["o]l.) The department of zo["o]logy which treats of the Crustacea (lobsters, crabs, etc.); -- called also malacostracology and crustaceology.
Wiktionary
malacostracology
n. (context obsolete English) carcinology, the study of crustaceans