from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A multicellular, often flask-shaped, egg-producing organ occurring in mosses, ferns, and most gymnosperms.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A multicellular reproductive structure that contains a large, non-motile gamete (egg cell), and within which an embryo will develop.
from the GNU version of the Collaborative International Dictionary of English
- n. The pistillidium or female organ in the higher cryptogamic plants, corresponding to the pistil in flowering plants.
from The Century Dictionary and Cyclopedia
- n. The pistillidium or female organ of the higher cryptogams, having the same function as the pistil in flowering plants.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a female sex organ occurring in mosses, ferns, and most gymnosperms
The archegonium is the female reproductive organ, which produces eggs.
The female organ in the bryophytes is called an "archegonium," and differs considerably from anything we have yet studied, but recalls somewhat the structure of the oögonium of _Chara_.
-- _A_, young embryo of _Funaria_, still enclosed within the base of the archegonium, × 300.
In this way it can be easily forced out of the archegonium, and then by thoroughly washing away the potash, neutralizing if necessary with a little acetic acid, very beautiful preparations may be made.
To study the first division of the embryo, it is usually necessary to render the archegonium transparent, which may be done by using a little caustic potash; or letting it lie for a few hours in dilute glycerine will sometimes suffice.
Shortly before the archegonium opens, the canal cells become disorganized in the same way as in the bryophytes, and the protoplasm of the central cell contracts to form the egg cell which shows a large, central nucleus, and in favorable cases, a clear space at the top called the "receptive spot," as it is here that the spermatozoid enters.
Finally the pollen tube penetrates down to and through the open neck of the archegonium, until it comes in contact with the egg cell.
The two growing points on the side of the embryo nearest the archegonium neck grow faster than the others, one of these outstripping the other, and soon becoming recognizable as the first leaf of the embryo (Fig. 67, _A_, _L_).
If a ripe archegonium is placed in water, it soon opens at the top, and the contents of the canal cells are forced out, leaving a clear channel down to the egg cell.
When very young the archegonium is composed of an axial row of three cells, surrounded by a single outer layer of cells, the upper ones forming five or six regular rows, which are somewhat twisted