from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The outer layer of cells of the spore-containing capsule of a moss.
from The Century Dictionary and Cyclopedia
- n. In botany, the layer of cells at first surrounding the endothecium in the capsule of a moss.
The lower tiers [v. 04 p. 0652] form the foot, while in the upper part the first divisions mark off the columella, around which the archesporium, derived from the amphithecium, extends.
The first periclinal division in the region forming the capsule separates an inner group of cells (the endothecium) form the peripheral layer (amphithecium).
In _Sphagnum_, as in _Anthoceros_, the archesporium is derived from the amphithecium; in all other mosses it is the outermost layer of the endothecium.