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bacteria live in an entirely anaërobic state, and which, like starch (amylum), is stained blue by iodine. (From this the generic names Amylobacter and Granulobacter, sometimes used, are derived.) They are provided with flagella (Fig. 134), and display active motion. When the spores develop, the rods swell out at one end and become club-shaped (Clostridium form) (Fig. 137). According to Prazmowski, the spores survive the temperature of boiling water for five minutes ; after ten minutes only a few of the strongest are alive, whilst all die in fifteen minutes. The species is strongly anaërobic.
Bacillus butyricus, Hueppe, differs from the above species in being aërobic.
Granulobacter saccharobutyricum, Beijerinck, is of general occurrence on barley corns, and therefore also on green malt, groats, flour, etc. It is one of the most injurious species in distilleries. It decomposes dextrose as well as maltose, and produces butyric acid, butyl alcohol, carbonic acid and hydrogen; gelatine is not liquefied by this species.
Bacillus lupuliperda, Behrens, is classified here inasmuch as it orms butyric acid when it is cultivated in a nutrient liquid containing sugar. Behrens found it in hops which had become warm. The cells are motile; they are 0.7 M to 2.5 u long and 0.7 u broad. It liquefies gelatine, and can be cultivated in an extract of hops. This bacillus is partly the cause of the spontaneous heating of hops, and forms trimethylamine and ammonia.
Finally, two bacilli have yet to be mentioned which cannot be classified in the above groups. One is
Bacillus piluliformans, Müller.Thurgau.-The rods are 3 u to 105 H long, most frequently 4 u to 6 m, and are 0.75 u broad. It causes in wine a remarkable disease described by Müller-Thurgau. In a red wine it had formed rounded corn-like grains, which clung to the sides of the bottle, but mostly to the bottom; these were in greater part detached by gently moving the bottle. The grains, of which as many as a hundred were found in a bottle, varied very much in size, some being hardly discernible, whilst others had a diameter of as much as 4.5 mm. The wine was of a darker colour than usual; its flavour and smell were but slightly altered ; it was clear, but not of good quality.
Bacillus subtilis, Ehrenberg. Hay bacillus.-It is found frequently
on hay. The spores are very resistant towards high temperatures ; according to Brefeld, they survive heating to 100° C. for three hours, to 105° C. for a quarter of an hour, and to 110° C. for five minutes. This species can therefore be obtained by pouring water over hay and boiling the liquor drawn off. The rods are strongly motile, and are furnished with several flagella. It first inverts cane sugar, and then oxidises it to the last trace. During its action on dextrose a strongly reducing lævo-rotatory body is formed (A. J. Brown).
This species is frequently met with in physiological fermentation work. It develops easily in unhopped wort; it does not thrive in acid liquids, and is on that account without significance in the brewery. According to Esaulow, it occurs in kefir ; it here participates in the formation of kefir grains, the film it forms on the milk serving as a collecting place for the lactic acid bacteria and yeast.
SECTION I. (Pages 1-15).
SPALLANZANI, LAZZARO : Saggio di osservazioni microscopiche, relative al sistema della generazione di signori Needham e
Buffon. Modena, 1765. II.—SCHEELE, Carl Wilhelm: Anmärkningar om sättet att conser
vera ättika. (Kongl. Vetenskaps Academiens nya Handlingar. Tom. iii. Stockholm, 1782, p. 120.)
III.--APPERT : Le livre de tous les ménages ou l'art de conserver
pendant plusienrs années, toutes les substances animales et végétales. 4ième éd. Paris, 1831.
IV.-SCHULZE, FRANZ: Vorläufige Mittheilung der Resultate einer
experimentellen Beobachtung über generatio æquivoca. (Poggendorff's Annal. d. Phys. u. Chem. Bd. xxxix., 1836.
No. 11, p. 487.) V.—CAGNIARD LATOUR, CHARLES : (1) His communication ap
peared in the Parisian “L'Institut” on 23rd November, 1836.
(2) Mémoire sur la fermentation vineuse. (Laid before the Académie des Sciences on 12th June, 1837; published in Compt. rend. de l'Acad. des Sc., Tom. iv., 1837, p. 905, and in Annal. de Chim. et Phys., Tom. Ixviii., 1838, p. 206.)
Cagniard Latour states in the above that yeast is organised matter and that it is probable that the formation of carbonic acid and of alcohol is caused in some way by the growth of the yeast.