. Plant life and plant uses; an elementary textbook, a foundation for the study of agriculture, domestic science or college botany. Botany. 408 THE NON-VASCULAR PLANTS In ferns you will find that the sporophyte ceases to have any nutritive connection with the gametophyte except when it is very young. It becomes an independent plant which makes its own food. It is the leafy part of the fern, while the gametophyte is an insignificant little structure which is rarely noticed. Finally, in seed plants, we find that sporophytes are the plants themselves, while the gametophytes, which began by being
. Plant life and plant uses; an elementary textbook, a foundation for the study of agriculture, domestic science or college botany. Botany. 408 THE NON-VASCULAR PLANTS In ferns you will find that the sporophyte ceases to have any nutritive connection with the gametophyte except when it is very young. It becomes an independent plant which makes its own food. It is the leafy part of the fern, while the gametophyte is an insignificant little structure which is rarely noticed. Finally, in seed plants, we find that sporophytes are the plants themselves, while the gametophytes, which began by being hosts of the parasitic sporo- phytes, end in seed plants by being themselves parasites, and the sporo- phytes are their hosts. You have already learned something of this in studying the flower. (See page 268.) Since a gradual increase of the sporophyte and a corresponding de- crease of the gametophyte is a univer- sal characteristic of the plant kingdom, we should naturally expect to find that there is some advantage to plants in this matter. This advantage is Fig. 204. — An antheridium not difficult to perceive. The thing of moss discharging its . . J. contents. At the left a whlch makes the sporophyte increase single sperm is shown, and become independent is that the Note that it has two cilia. mtd^& WQrk of ^ plant> &t first done by the gametophyte, is gradually transferred to the sporophyte, while the thing which makes the gametophyte decrease in importance is that it loses this nutritive work. As you have noted, the sporophyte of lower plants gets its food from the gametophyte, while in the higher plants gametophytes get their food from Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coulter, John G. (John Gaylord), b. 1876. New York, American Book Co
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