Porina, [518], [527], [529]

Potamilla, [338]

Praeoral lobe (= Prostomium), [245], [439]

Predaceous worms, [304]

Priapuloidea, [412], [446];

anatomy, [430];

classification, [432];

habits, [433]

Priapulus, [430], [431], [432];

anatomy, [430] f.