. A handbook of cryptogamic botany. Cryptogams. 354 FUNGI layer of protoplasm coating the wall. At this stage the full growth of the ascus is commonly reached, and the formation of ascospores begins with the division of the nucleus into two ; then by the same process four appear, then eight, which in the majority of cases represents the number of ascospores. In many Ascomycetes, however, other numbers typically prevail, one, or two, or four, or sixteen, forty, fifty, and so on to over a hundred. Dothidea (Fr.), for example, has two to four, Sor- daria (Ces. and De Not.) four, sixteen, six
. A handbook of cryptogamic botany. Cryptogams. 354 FUNGI layer of protoplasm coating the wall. At this stage the full growth of the ascus is commonly reached, and the formation of ascospores begins with the division of the nucleus into two ; then by the same process four appear, then eight, which in the majority of cases represents the number of ascospores. In many Ascomycetes, however, other numbers typically prevail, one, or two, or four, or sixteen, forty, fifty, and so on to over a hundred. Dothidea (Fr.), for example, has two to four, Sor- daria (Ces. and De Not.) four, sixteen, sixty-four, and one hundred and twenty-eight. Whatever the number, the nuclei always possess the same. Fig. 300.—Peziza {Pyronetnd) conflue-ns P. a, small portion of hjjmenium ; p, paraphyse attached" to, not originating in, hyphal branches from which the three asci spring ; 7«, young asci ; ?—70, successive stages, according to letters, in the development of ascospores within asci ( x 390). (After de Bar>'.) structure in all stages of multiplication, but they become smaller in size as the number advances. Round each nucleus there gathers a clear mass of protoplasm, and ultimately this becomes enclosed by a mem- brane, aiid, growing in size, thus develops into a spore. The ascospores are arranged in a series, one over the other within the ascus. The protoplasm left over within the ascus and outside the sporej differs from that within the spores in exhibiting a reddish or violet-brown colour after treatment with iodine solution. De Bary originally proposed the -term ' epiplasm' for this portion of the contents; but, Errera 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 Bennett, Alfred W. (Alfred William), 1833-1902; Murray, George Robert Milne, 1858-. London, New York, Longmans, Green, and
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