. Plant studies; an elementary botany. Botany. TllALLOl'II YTKS : FUNGI 27£. a littlo sphere, which suggested the nanio MicfiiKplui'ni (l''ig. 241). The heiivy wall of the ascucarp bears beauti- ful branching hair-lilce appendages (Fig. 342). Bursting the wall of tliis spore fruit several very delicate, bladder-like sacs are extruded, and through the transparent wall of each sac there may be seen several spores (Fig. 24'i). The ascocarp, there- fore, is a spore case, just as is the cystocarp of the Ked Alga3 (S 174). The delicate sacs within arc the , a word meaning " sacs," and
. Plant studies; an elementary botany. Botany. TllALLOl'II YTKS : FUNGI 27£. a littlo sphere, which suggested the nanio MicfiiKplui'ni (l''ig. 241). The heiivy wall of the ascucarp bears beauti- ful branching hair-lilce appendages (Fig. 342). Bursting the wall of tliis spore fruit several very delicate, bladder-like sacs are extruded, and through the transparent wall of each sac there may be seen several spores (Fig. 24'i). The ascocarp, there- fore, is a spore case, just as is the cystocarp of the Ked Alga3 (S 174). The delicate sacs within arc the , a word meaning " sacs," and each ascus is evidently a mother cell within which asexual spores are formed. These spores are distin- guished from other asexual spores by the name xpnrc. it is these peculiar moth- er cells, or asci, which give name to the group, and an Ascomycete, Ascus-fuugus, or Sac-fungus, is one which produces spores in asci; and an ascocarp is a spore case which contains asci. In the mildews, therefore, there are two kinds of asexual spores : (1) coiiUHh, formed from a hyphal branch by aljstric- tiou, by which the mycelium may spread rapidly; and (2) asmspores^ formed in a mother cell aiul protected liy a heavy case, so that they may bridge over unfavorable conditions, and may germinate when liberated and form new mycelia. The resting stage is not a zygote or an oospore, as in the Algie and Phycomycetes, no sexual spore probably being formed, but a heavy-wallcd ascocarp. 185. Other forms.—The mildews have been selected as a simple illustration of Ascomycetes, but the group is a very Fio. 242. Ascocarp of the lilac mildew, showing brandling appendages and two asci protriulinj^ from the ruptured wall and containing ascospores,—S. M. 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 Coulter, John Me
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1900
