. Introduction to botany. Botany. 296 Introduction to Botany. constitution of the nu. Fig. 158. Diagrams of the sporophyte and gametophyte of a moss. The spore n produced asexu- ally in the capsule m (which with its stallc / is the sporo- phyte) is the beginning of the gametophyte. All of the gametophyte produced by the germination of the spore is shaded; all of the sporo- phyte is left unshaded, p in ^, the protonema from which springs the moss plant g (gametophyte together with p), bearing an archegonium {s) with its egg, and an an- theridium(?')with its sperms. B, a later stage, the capsule
. Introduction to botany. Botany. 296 Introduction to Botany. constitution of the nu. Fig. 158. Diagrams of the sporophyte and gametophyte of a moss. The spore n produced asexu- ally in the capsule m (which with its stallc / is the sporo- phyte) is the beginning of the gametophyte. All of the gametophyte produced by the germination of the spore is shaded; all of the sporo- phyte is left unshaded, p in ^, the protonema from which springs the moss plant g (gametophyte together with p), bearing an archegonium {s) with its egg, and an an- theridium(?')with its sperms. B, a later stage, the capsule or sporophyte having sprung from the fertilized egg. cleus of the fertilized egg is doubled by this union, so that the fertilized egg contains the same number of chromosomes as do the nuclei of the cells which make up the body of the fern plant or sporophyte springing from the fertilized egg. Therefore we look upon the ferti- lized egg as the one-celled stage of the sporophyte. When the moss spore (Fig. 158, ii) germinates, a multicellular body is produced (protonema, p') from which springs the moss plant (^g) bearing antheridia (r) and arche- gonia (i-) at its summit. Evidently, therefore, the entire body resulting from the germination of the spore is the gametophyte. The egg after fertilization produces the slender stalk (/) and capsule {ni), namely, all of the unshaded part of Fig. 158, B, which must be the sporo- phyte, since it is produced in the same manner (namely, from the fertilized egg within the archego- nium) and has the same position in the life cycle as has the fern plant in the life cycle of the fern. It is true that the stalk and capsule appear to be an organic part of the moss plant, but from the evidence before us we must conclude that. 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 Steve
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