. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. 422 SECOND PART.—MrCETOZOA. without success. Germination takes place under conditions which will be more particularly related in a subsequent page; in most species when the spores are placed in water. The germinating spore (Fig. 182) swells first of all by absorption of water, and one or two small vacuoles, which disappear and reappear alternately, are seen near the upper surface of the protoplasm in which rotating movements are often observed; at length, and usually
. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. 422 SECOND PART.—MrCETOZOA. without success. Germination takes place under conditions which will be more particularly related in a subsequent page; in most species when the spores are placed in water. The germinating spore (Fig. 182) swells first of all by absorption of water, and one or two small vacuoles, which disappear and reappear alternately, are seen near the upper surface of the protoplasm in which rotating movements are often observed; at length, and usually 12-24 hours after the scattering of the spores, the membrane bursts and the protoplasm oozes or creeps slowly out of the opening. The protoplasmic body then either at once, as is the rule, or after a transitory period of rest, during which it assumes a spherical form, commences amoeboid movements, undulating changes of outline and protrusions and withdrawals of pointed processes, and in this way becomes elongated into a body which moves about in the water like a swarm-spore and is known by the name oi swarm-cell (Fig. 182 d-f^. The swarm-cell has the same structure as the protoplasmic body before it emerged from the spore, only that the granules in the protoplasm are collected together in the larger part of the cell, which is the hinder part in the movement, while the anterior part is free from granules and also contains the nucleus. From one to three vacuoles lie in the posterior part, one of which at least is known as the contractile vesicle, because in about a minute's time it grows smaller and disappears, and then reappears and enlarges till it is one third or one half the breadth of the protoplasmic body. The granules or lumps of mucilage in the spore either continue in the swarm-cell, or they are dissolved before the protoplasm leaves the spore, or they are extruded and left behind within the membrane. The swarm-cell has no firm membrane, but careful observation shows t
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