Akademik

sessile
adjective
a) permanently attached to a substrate; not free to move about; “an attached oyster”

The sporophyte foot is also characteristic: it is very broad and more or less lenticular or disciform, as broad or broader than the calyptra stalk, and is sessile on the calyptra base

b) attached directly by the base; not having an intervening stalk.
Syn: attached, fixed, immobile
Ant: mobile

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