in Gymnosperms (like Pinus), the male and female gametophytes do not have an independent free-living existence and remain within the sporangia retained on the sporophytes . In contrast, in Bryophytes (Marchantia, Polytrichum), the gametophyte is the dominant, free-living phase , . In Pteridophytes (Adiantum), the gametophyte is a free-living, photosynthetic thalloid called a prothallus .