Mazzaella flaccida (was Iridaea) Life History Scrapbook
Notice how the carposporophyte on the left has tattered. The trouser tear test revealed that the carposporophyte is weakest towards its stipe. The carposporophyte on the left, like many I observed on the Monterey coast, experienced tattering on the lower part of its blade first. The carposporophyte on the right has almost completely tattered, but you can still see that the middle of the blade rather than the tip seems to have disintegrated most quickly.
Click on the picture of this carposporophyte to view it larger. See
what happens when the sorus is sectioned more thinly and its carpospores explode from
their tight packing.
Each of the round bodies is a carpospore; the group of them composes the carposporangium. The upper right corner of the photo shows Iridaea's fillamentous medulla while the cortex, or surface cells, are just visible in the lower left corner.
Notice the smooth margins or the tetrasporophyte which lack tetrasporangia, the dark dots.
These prize pictures show the last stage of Iridaea's life history. The first depicts a tetrasporanial sorus, or tetrasporangium, located on the blade of the tetrasporophyte. Just visible are round lumps, tetraspores, which have four 1n spores. The last photo, captured from videotape, provides a closeup view of one of these cruciate tetraspores.