Practical bacteriology for chemical students / by David Ellis.

  • David Ellis
Date:
1923
Catalogue details

Licence: In copyright

Credit: Practical bacteriology for chemical students / by David Ellis. Source: Wellcome Collection.

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    MOULDS. Examination of impure Mucor: Examination of impure Penicillium: Germination of spores: Methods of spore- location: Pure culture of Mucor mucedo: Culture-media for Fungi: Identification of commoner Moulds: Acidity- changes produced by moulds: Infection of fruit with mould. Moulds. The term mould is not given to any particular group of Fungi but is rather a popular term to indicate different fungi which externally are very much alike especially to those who have not made a special study of these organisms. All 'fluffy' growths are usually called moulds. On culture media moulds form colonies that are made up of very tiny threads called hyphae and under the low power of the microscope these hyphae are seen to branch and anastomose. The colony is thus easily distinguished from those that are formed by bacteria or by yeasts. The student should study a single species of mould with the same care and essentially in the same manner as was necessary in the study of bacteria and yeasts. Moulds form spores as do the bacteria: in fact the iden- tification of the different species largely depends on the mode of formation of these reproductive bodies. In the majority of cases the student will find that a species which appears on his cultures is either a Mucor or a Penicillium. The former is distinguished by the formation of spores inside a receptacle called a sporangium (Fig. 44). Usually the membrane of the sporangium bursts