. Introduction to the study of fungi, their organography, classification, and distribution for the use of collectors . e cells likecylinders, closely packed side by side,their apices terminating in the disc,and their bases being seated upon theinner surface of the excipulum (Fig. 70).In due time these cylindrical sacs, or asci,contain four or eight, or some multipleof that number, of smaller bodies, whichare the spores or sporidia—the repro-ductive corpuscles of the Fungus. Insome cases the apex of the ascus opens Fig. 69.—Cup of Peziza, with -^^ means of an operculum, or small section and asc
. Introduction to the study of fungi, their organography, classification, and distribution for the use of collectors . e cells likecylinders, closely packed side by side,their apices terminating in the disc,and their bases being seated upon theinner surface of the excipulum (Fig. 70).In due time these cylindrical sacs, or asci,contain four or eight, or some multipleof that number, of smaller bodies, whichare the spores or sporidia—the repro-ductive corpuscles of the Fungus. Insome cases the apex of the ascus opens Fig. 69.—Cup of Peziza, with -^^ means of an operculum, or small section and ascus. v i t, . - u i, • i lid, but at others by an irregular rup-ture, to permit of the escape of the spores. Mixed withthese spore-bearing sacs will be found a number of longthread-like bodies of equal length, or longer than the asci, andthese are termed, jparcqjliyses. Some mycologists believe themto represent abortiveasci, and this is sup-ported by the fact thatnow and then a para-physe is observed whichencloses one or two like the normal of the Fungus. the Peziza is and the cup is spores,sporesWhenyounf. Fig. 70.—Section of cup of Ascuhulus. closed, all the cylindri-cal cells are narrow, thread-like, and empty ; but as growth pro-ceeds and sporidia begin to form, the diameter of the cellsincreases, and, as a consequence, the disc enlarges and expandswith the lateral pressure so as to occasion the flattening out ofthe cup. When there is a great expansion the edges of the cupare either split or bent back, so that the disc becomes convex,all these modifications being due to the thickening of the asci. DISCOID FUNGI—DISCOMYCETES 175 With such a structure it will manifestly be almost im-possible to trace the development of the spore and to set atrest the question of sexuality in reproduction. It has beenassumed that there is some form of impregnation in the Dis-comycetes, either for each individual ascus or for the entirecup. Those who have advocated the impregnation of
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