. The microscope and its revelations. those whosemultiplication is broughtabout by the formationwithin a cell of a minuteglobular or oval body,which, while the sur-rounding protoplasm ofthe mother-cell is assimi-lated, gradually reachesits mature it is that exactlydetermines the act ofspore-formation is notknown, but it is probablethat free access to oxygenconstitutes an importantfactor. A chosen illustrationof the endosporous Bac-tf-rla is Bacillus meyrt-therium. It was first observed 011 boiled cabbage leaves, and is considered by De Bary asan exceedingly instructive form. It
. The microscope and its revelations. those whosemultiplication is broughtabout by the formationwithin a cell of a minuteglobular or oval body,which, while the sur-rounding protoplasm ofthe mother-cell is assimi-lated, gradually reachesits mature it is that exactlydetermines the act ofspore-formation is notknown, but it is probablethat free access to oxygenconstitutes an importantfactor. A chosen illustrationof the endosporous Bac-tf-rla is Bacillus meyrt-therium. It was first observed 011 boiled cabbage leaves, and is considered by De Bary asan exceedingly instructive form. It is 25/i in short diameter andabout four times as long as this. It is illustrated in fig. 489. a re-presents a motile chain of the Bacilli in active vegetation. This ismagnified 2)0 diameters, b two active rods magnified 600 diameters.•p shows the result of treating a form in the condition b with analcoholic solution of iodine, c is a rod with five cells preparing toform spores, d to/represent successive stages of a pair of rods in. FIG. 488.—Beggiatoa, alba, curved and spiralforms. (From De Barys Comparative Morpho-logy of Fungi.) 656 FUNGI the act of forming spores, e an hour later than d, and _/ an hourlater than e. The cells which did not contain spores disappeared orperished. r is a quadricellular rod with ripe spores, t/1 is a five-celled i-od with three ripe spores placed in a nutrient solution after several days desiccation, y- is thesame an hour after ; </3 is the sameafter another two hours and a ! is two spores with the walls ofthe mother-cells dried and placed ina nutrient solution ; is the sameforty-five minutes later ; /, k, I, threestages of germination of the spore. Bacillus anthracis and R. snbtili*are very typical examples of endo-sporous bacteria. B. anthracis hasbeen proved to be the virus ofanthrax or splenic fever. It isfound in great profusion in theblood and tissues of animals attacked(From De Barys SpttS % ^ disease in the form of rods
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