. Our native ferns and their allies; with synoptical descriptions of the American Pteridophyta north of Mexico. Ferns; Pteridophyta. Fig. 14.—Antheridium of Adixxtum Fig. is.—Young archegonium of Pteris capilluS'Veneris L., showing the es- serrulata Linn, f., showing oSsphere, caping antherozoids. (After Sachs.) neck, and canal-cell. (After Sachs.) and retaining the antherozoids at the neck of the archegonium. The oOsphere is thus left exposed (Fig. 15). 65. Fertilization.—The antherozoids, analogous to the sperm-cells, when discharged from the antheridium swim in the moisture always present o
. Our native ferns and their allies; with synoptical descriptions of the American Pteridophyta north of Mexico. Ferns; Pteridophyta. Fig. 14.—Antheridium of Adixxtum Fig. is.—Young archegonium of Pteris capilluS'Veneris L., showing the es- serrulata Linn, f., showing oSsphere, caping antherozoids. (After Sachs.) neck, and canal-cell. (After Sachs.) and retaining the antherozoids at the neck of the archegonium. The oOsphere is thus left exposed (Fig. 15). 65. Fertilization.—The antherozoids, analogous to the sperm-cells, when discharged from the antheridium swim in the moisture always present on the under surface of the prothallium, swarm in large numbers around the neck of the archegonium, and are retained by the mucilage. Sorne finally force their way into the canal of the neck, a few reaching the oosphere and disappearing within its substance. There is thus a true sexual generation among ferns, and the formerly appro- priate term Cryptogamia (hidden marriage) loses its application under the untiring scrutiny of the microscopist. After fertili- zation the neck of the archegonium closes, and the fertilized. 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 Underwood, Lucien Marcus, 1853-1907. New York, H. Holt
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