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Hepatophyta-Metzgeriales-2 |  |
| Sexual ReproductionAntheredia are produced on the dorsal surface
in Mound-Like Projections called "Perigonia".
Archegonia are also produced on the dorsal surface but are covered by an Involucral Flap. Other protective outgrowths are also present. These are called "Perichaetial Scales". A Calyptra also develops from the Archegonia after Syngamy. While multiple fertilzations are possible, there is generally only one Sporophyte produced by each Thallus segment.Does this have adaptive significance? |
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The Sporophyte is Similar to Marchantia |
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Gametophytes with Young Sporophytes |
 Riccardia Sporophyte inside Calyptra |
 Mature Sporophyte breaking through the Calyptra |
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of the Sporophyte is provided by the Involucre, Perichaetial Scales" & Calyptra.
Development can be arrested during harsh periods. This has obvious adaptive value because spore release can be delayed until conditions are advantageous.
The MeioSpores are Chlorophyllous. This is thought to be an Ancestral trait because the resulting Gametophyte will require light in order to survive.
There are some mitotic divisions before the spore germinates this is called Endosporic Development & is considered to be an advanced trait because a multicellular organism has a greater chance to survive & mature than a unicellular one. The Spores are Heavy, however, and they require free H2O for Dispersal. This is a disadvantage! Why???Elaters are present and in some cases they are attached to inner Capsule Wall.They can have an Egg Beater-like action which helps to disperse the Spores.
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