Elementary botany (1898) Elementary botany . elementarybotany00atki Year: 1898 Fig. 174. Nearly mature sporogonium of Riccia crystallina; Fig. 175- Riccia glauca; archegonium containing nearly mature spo- rogonium. sg\ spore-producing cells surrounded by single layer of sterile cells, the wall of the sporogonium. mature spore at the right fours are the spores. At this time the wall of the spore-case dis- solves, the spores separate from each other and fill the now en- larged venter of the archegonium. When the thallus dies they are liberated, or escape between the loosely arranged cells of th
Elementary botany (1898) Elementary botany . elementarybotany00atki Year: 1898 Fig. 174. Nearly mature sporogonium of Riccia crystallina; Fig. 175- Riccia glauca; archegonium containing nearly mature spo- rogonium. sg\ spore-producing cells surrounded by single layer of sterile cells, the wall of the sporogonium. mature spore at the right fours are the spores. At this time the wall of the spore-case dis- solves, the spores separate from each other and fill the now en- larged venter of the archegonium. When the thallus dies they are liberated, or escape between the loosely arranged cells of the upper surface. 314. A new phase in plant life.—Thus we have here in the sporogonium of riccia a very interesting phase of plant life, in which the egg, after fertilization, instead of developing directly into the same phase of the plant on which it was formed, grows into a quite new phase, the sole function of which is the development of spores. Since the form of the plant on which the sexual organs are developed is called the gametophyte^ this new phase in which the spores are developed is termed the sporo- phyie. Now the spores, when they germinate, develop the gameto- phyte, or thallus, again. So we have this very interesting condi-
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