1. (fibrous layer) In angiosperms, the layer of cells lying beneath the epidermis of the wall of the anther. As the anther matures, thickenings often develop in the cell walls of the endothecium, probably aiding dehiscence.
2. In Bryophyta, the inner layer of cells in the young sporophyte.
"endothecium." A Dictionary of Plant Sciences. . Encyclopedia.com. (August 18, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/endothecium
"endothecium." A Dictionary of Plant Sciences. . Retrieved August 18, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/endothecium