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Webster 1913 Edition
Acephala
‖
A-ceph′a-la
,Noun.
pl.
[NL., fr. Gr. [GREEK], adj. neut. pl., headless. See
Acephal
.] (Zool.)
That division of the Mollusca which includes the bivalve shells, like the clams and oysters; – so called because they have no evident head. Formerly the group included the Tunicata, Brachiopoda, and sometimes the Bryozoa. See
Mollusca
.