. Microbes & toxins. Bacteriology; Toxins; Antitoxins. 58 MICROBES AND TOXINS limited by the quantity of available nourishment and by the accumulation of the products of excretions ; the cultures end by poisoning themselves. But even in a drop of culture medium, the energy of multiplications is enormous. One filament of the Bacillus ramosus studied by Marshall Ward doubled its length in thirty-five minutes; in twelve hours a single bacillus produced four millions, and one piece of one- hundredth of a millirnetre in length produced in twelve,hours the equivalent of a thread of 40 metres. Pa
. Microbes & toxins. Bacteriology; Toxins; Antitoxins. 58 MICROBES AND TOXINS limited by the quantity of available nourishment and by the accumulation of the products of excretions ; the cultures end by poisoning themselves. But even in a drop of culture medium, the energy of multiplications is enormous. One filament of the Bacillus ramosus studied by Marshall Ward doubled its length in thirty-five minutes; in twelve hours a single bacillus produced four millions, and one piece of one- hundredth of a millirnetre in length produced in twelve,hours the equivalent of a thread of 40 metres. Pasteur followed under the,microscope the growth of the yeast of wine in grape juice at 13° C. One globule produced 10 millions in twenty- four hours when nothing intervened to limit its development. It is easy to understand now how the infinitely minute grows to form a mass and brings into play enormous forces. Spores.—Certain bacteriaproducesporeSjthespore appearing as a shining point in the filament ; the protoplasm of'the cell diminishes as the young spore increases, as bacterium if sporulations were a condensa- tion of the living matter. Later the remoGisjf the spore bacillus disappears and the spore is free. Being en- closed in a resist- „ . , . , ing sheath the r IG. 27.—Various types of germmation of spores. , , I. The spore germinates by growth in all spore resembles a dimensions. 2. Germination by a sort of seed, capable of terminal budding. 3. The spore germinating nrnlnno-prl nrP by a sort of lateral budding. (After De Bary Proiongea pre- and Prazmowski.) servation and of sprouting into a new bacillus when the conditions become favourable. It is by means of their spores that the bacilli of tetanus and of anthrax persist so tenaciously in nature. The anthrax bacillus is killed by heating to 60° C, the spore not till after three minutes' boiling at iqo° Please note that these images are extracted from scanned page images that may have been digitally enhance
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