. Comparative morphology of Fungi. Fungi. Fig. 147.—Polystigma rubrum. 1. Section through portion of leaf with young pyc- nium. 2. Section through young perithecial fundament showing helical ascogonium. 3. Pycnospores. (1 X 200; 2 X 600; 3 X 1,200; after Blackman and Welsford, 1912.) The pyenidial wall consists of a plectenchyma from which the sporiferous hyphal branches radiate (Fig. 147, 1). The pycnospores are terminal, uninucleate, tapering upward and falcate at their tips (Fig. 147, 3). They are embedded in a slimy substance and in damp weather are forced out of the mouth of the pyenia up
. Comparative morphology of Fungi. Fungi. Fig. 147.—Polystigma rubrum. 1. Section through portion of leaf with young pyc- nium. 2. Section through young perithecial fundament showing helical ascogonium. 3. Pycnospores. (1 X 200; 2 X 600; 3 X 1,200; after Blackman and Welsford, 1912.) The pyenidial wall consists of a plectenchyma from which the sporiferous hyphal branches radiate (Fig. 147, 1). The pycnospores are terminal, uninucleate, tapering upward and falcate at their tips (Fig. 147, 3). They are embedded in a slimy substance and in damp weather are forced out of the mouth of the pyenia upon the leaf. Later, in July or August, the perithecium is formed, as a small hyphal tangle in which is embedded a helical ascogonium (Fig. 147, 2). Its development is incompletely known; a half schematic cross section of an older stage is shown in Fig. 148, 1. The basal cell of the ascogonium bordering on the ascogonial hypha is short and has few nuclei. Adjacent to it is an elongated cell with many small nuclei. The next cell has only a single, rather large nucleus but is much shorter than both the previous ones. There follow two cells with two small nuclei each; then the helix continues with cells with an irregular number of nuclei and finally is lost. 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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Keywords: ., bookcentury1900, bookdecade1920, bookpublishern, booksubjectfungi
