. Botany for high schools. Botany. OTHER FERN-LIKE PLANTS: CLUB MOSSES 349 Spores, which means large spores. The upper spore cases produce a very large number of small spores {microspores). Since the spores are of different sizes, Selaginella is said to be a heterosporus plant. A plant is homosporus when the spores are all alike. 518. The prothallia or gamete plants (gametophytes) of Selaginella.—The gamete plants of Selaginella are dicx'ceous (or heterothallic). This condition of the prothallium is deter- mined in the spore. The small spores (microspores) pro- duce small male gamete plants. T
. Botany for high schools. Botany. OTHER FERN-LIKE PLANTS: CLUB MOSSES 349 Spores, which means large spores. The upper spore cases produce a very large number of small spores {microspores). Since the spores are of different sizes, Selaginella is said to be a heterosporus plant. A plant is homosporus when the spores are all alike. 518. The prothallia or gamete plants (gametophytes) of Selaginella.—The gamete plants of Selaginella are dicx'ceous (or heterothallic). This condition of the prothallium is deter- mined in the spore. The small spores (microspores) pro- duce small male gamete plants. There is only one cell in the prothallium part. The other cell, which is larger, develops into the sperm case with a wall containing a few sperms. The sperms are biriliate, as they are in the lycopods, thus being different from those of the ferns and horsetails, and more like those of the mosses. The large. 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 Atkinson, George Francis, 1854-1918. New York, H. Holt and Company
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1910
