In Bryophytes, archegonium is the female sex organ. The female shoot arises from the base of the male shoot and called an archegonial branch or archegoniophore. The apex of female shoot is called the female receptacle from which a cluster of archegonia arise intermixed with non-capitate paraphysis.
Each archegonium has a stalk, flask-shaped center, and a neck. Venter encloses a basal egg cell (oosphere) and an upper smaller venter canal cell. The neck consists of 6 or more neck canal cells (6-11).
