In funaria sporophyte the zygote as a result of divisions from eight outer cell encirching four inner cells. Outer cells form endotherium and inner cells form endotherium. Endotherium cells divide by perichimical divisions to form an outer endothecium and inner endothecium cells which give rise to Columella, while outer endotherium cells form archesporium which is superficial in position and surrounds columella from all sides. Entire aschesporium of sporogenous cells forms spore mother cells which divide by meiosis to form haploid advanced. It is differentiated into foot embedded in the tissue of female shoot, a thin long seta and a pear shaped capsule.
Capsule when mature is cap shaped operculum at top. Below operculum is peristome which peristomial teeth are present. There is central columella covered by a spore sac. Near spore sac, the air spaces are present. Wall of capsule is multilayered. Lower part of capsule or apoplysis has conducting strand and epidermis of this region has stomata. In dry conditions the cells of annulus shrink, operculum sheds off, peristomial teeth open and spores were liberated out. These spores are carried to long distances by wind and germinate in favourable conditions.
Riccia sporophyte:
In riccia the zygote by divisions becomes multi-cellular structure. At this stage the embryo divides by pericinal wall into outer amplithecium and inner endothercium. In this case endothercuim is the first cell generation (archesporium) of the sporogenoous tissue or it is formed from entire endothecuim and is centrally situated.
Amlithecuim forms a single layered Jacket.
By repeated divisions the archegonuim transforms into sporogenous cells which function as spore mother cells, most of which form spores haploid after reduction division except a few called as nurse cells which degenerate afterwards and serve as a nutritive tissue. The sporophyte in case of Riccia represents the simplest structure among Bryophytes as it has only a capsule with jacket and spores. There is no foot seta and no fertilization of sporogenous tissue in the capsule. Spores get liberated free immediately after they are mature by progressive death and decay of surrounding tissue of the thallus.
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