conceptacle
1. An urceolate cavity in which gametes are formed. It is found inside the inflated tip of the thallus of certain brown algae (e.g. Fucales), and has a small opening called the ostiole. See also RECEPTACLE (3).

2. In the thallus of some members of the Phaeophyta, a cavity in which gametangia (see gametangium) are formed.

conceptacle A flask-shaped cavity with a small opening (the ostiole) that is found in the swollen tip of certain brown algae, such as Fucus. It contains the sex organs.