. Botany for secondary schools; a guide to the knowledge of the vegetation of the neighborhood. Plants. 345. Spores of mucor; some germinating. Mould.—One of these moulds, Mucor mucedo, which is very com- mon on all decaying fruits and vegetables, is shown in Fig. 344, some- what magnified. When fruiting, this mould appears as a dense mass of long white hairs, often over an inch high, standing erect from the fruit or vegetable upon which it is growing. The life of this mucor begins with a minute rounded spore (a, Fig. 345), which lodges on the decaying material. When the spore germinates, it s
. Botany for secondary schools; a guide to the knowledge of the vegetation of the neighborhood. Plants. 345. Spores of mucor; some germinating. Mould.—One of these moulds, Mucor mucedo, which is very com- mon on all decaying fruits and vegetables, is shown in Fig. 344, some- what magnified. When fruiting, this mould appears as a dense mass of long white hairs, often over an inch high, standing erect from the fruit or vegetable upon which it is growing. The life of this mucor begins with a minute rounded spore (a, Fig. 345), which lodges on the decaying material. When the spore germinates, it sends out a delicate thread which grows rapidly in length and forms very many branches which soon permeate every part of the substance on which the plant grows, (b, Fig. 345.) One of these threads is termed a hypha. All the threads together from the mycelium of the fungus (194). The mycelium disorganizes the material in which it grows, and thus nour- ishes the mucor plant. (Fig. 344.) It corresponds physiologically to the roots and stems of other plants. When the mycelium is about two days old, it begins to form the long fruiting stalks which we first noticed. To study them, use a compound microscope magnifying about two hundred diameters. One of the stalks, magnified, is shown in Fig. 346, a. It consists of a rounded head, the sporangium, sp, supported on a long, delicate stalk, the sporangiophore, st. The stalk is separated from the sporangium by a wall which is formed at the base of the sporangium. This wall, how- ever, does not extend straight across the thread, but it arches up into the sporangium like an inverted pear. It is known as the columella, c. When the sporangium is placed in water, the wall immediately ruptures and allows hundred of spores, which were formed in the cavity within the sporangium, to escape, b. All that is left of the fruit is the stalk, with the pear-shaped columella at its summit, c. The spores which have been set free by the breaking of the spor
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1913
