Introduction to the study of fungi : their organography, classification, and distribution for the use of collectors . small sectiou and ascus. ,. i , , , , i 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 faraijiihyses. 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 twospores, like the normalspores of t
Introduction to the study of fungi : their organography, classification, and distribution for the use of collectors . small sectiou and ascus. ,. i , , , , i 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 faraijiihyses. 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 twospores, like the normalspores of the the Pcziza isyoung, and the cup isclosed, 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 Fig. 70.—Sectiou of cup of Ascobolus. 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 the asci,affect to see in the paraphyses some representative of the maleorgans, but in support of this theory there is no evidence. Thegranular contents at the apices of the paraphyses do notsuggest spermatia, but mostly colouring matter which impartsthe tone of colour to the disc. Advocates have also been foundfor the fertilisation of the entire cup in its most initial stageof growth. These profess to have found, especially in Ascobolusfiirfuraceus and in Pyronem
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Keywords: ., bookauthorcookemcm, bookcentury1800, bookdecade1890, bookyear1895
