. Comparative morphology of Fungi. Fungi. 128 COMPARATIVE MORPHOLOGY OF FUNGI Because of a peculiar weakening of sexual tendencies in the Ascomy- cetes, plasmogamy early loses it obligatory character and becomes facultative. This functional disturbance first affects morphologically only the antheridia: these become superfluous and disappear, and instead of amphimictic fertilization, appear all sorts of deuterogamous processes which we shall later follow in detail under the individual orders. Gradu-. Fig. 78.—Pyronema conflucns. Sexual organs. Antheridium, Anth, and ascogonium, arch, with trich
. Comparative morphology of Fungi. Fungi. 128 COMPARATIVE MORPHOLOGY OF FUNGI Because of a peculiar weakening of sexual tendencies in the Ascomy- cetes, plasmogamy early loses it obligatory character and becomes facultative. This functional disturbance first affects morphologically only the antheridia: these become superfluous and disappear, and instead of amphimictic fertilization, appear all sorts of deuterogamous processes which we shall later follow in detail under the individual orders. Gradu-. Fig. 78.—Pyronema conflucns. Sexual organs. Antheridium, Anth, and ascogonium, arch, with trichogyne, t. (X 1,750; after Claussen, 1912.) ally, however, this functional degeneration extends to the female organs; they also degenerate and disappear. Eventually no organ is formed and the plasmogamy becomes pseudogamous. Hand in hand with this degeneration, there also appears a shifting of the significance of the sexual organs for the formation of fructifications. Originally the laying down of the fructifications was begun by the formation of sexual organs; hence the female organ was called archicarp. In many higher forms, the fructifications begin their development inde-. 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 Gäumann, Ernst Albert, 1893-1963; Dodge, Carroll William, 1895-. New York [etc. ] McGraw-Hill Book Company, Inc.
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