Both shagnum and ptris have dependent diploid stage. Shagnum is Bryophyta and pteris is pteridophyta. So, Bryophytes and Pteridophytes show an intermediate condition called the haplo-diplontic life cycle, where phases are multicellular. But the dominant phase differs. In Bryophytes, the dominant phase is the gametophyte and in Pteridophytes, it is the sporophyte.