Dryopteris filix-mas, enlarged approximately 45 times. One group each of antheridia and archegonia are on the underside of the prothallium, as well as numerous rhizoids that serve to anchor it to the ground. A small fern has developed from the fertilized egg cell of an archegonium. It consists of a juvenile leaf and a first root. In one piece. On a stand with a base and explanatory note.