Flosculariidae, [201], [203], [205], [220] n., [221], [230]

Flukes, [51]

Flustra, [465], [466], [467], [472], [473], [477], [515], [518], [526];

avicularia, [482]

Flustrella, [467], [477], [518], [532];

larva, [513]

Flustrina, [518]

Food, of Turbellaria, [4];

of Leptoplana, [10];

of Polyclads, [24];