248 SACCHAROMYCETES. 



dopterous insects sent him from abroad, will possibly interest the 

 readers of this Journal. 



It will be generally known to the scientific reader that alcoholic 

 fermentation can be brought about in suitable liquids by many 

 organisms other than the Saccharomycetes. The veteran inves- 

 tigator — Pasteur — has shown, in a work published in Paris in 

 1876*, that aspergillus, and the variety which he describes as /^rz/:/^?, 

 are both able to produce alcoholic change in saccharine liquids. 

 Rees, long since, investigated in Germany the conditions under 

 w^hich niucor racemosus becomes an alcoholic ferment, and Brefeld 

 has done the same service in respect of others of the mucorini, thus 

 placing it beyond question that the power of producing alcoholic 

 fermentation cannot be looked upon as belonging to any one class, 

 or as in any degree constituting a basis of classification. Indeed^ 

 recent researches of Pasteur seem to show that it is not improbably 

 a property inherent in the vegetable cell, and capable of being 

 brought into action in the case of some phanerogamic plants by a 

 mere change in their environment. 



It became, then, necessary to seek for a fresh starting point 

 whence to approach the classification of these difficult organisms, 

 and Rees, again taking up the work, and bearing in mind the 

 modern scientific axiom that no classification can be considered 

 of value until the entire life-history of the individual, from one 

 generative act to another, is accurately known, determined to w'ork 

 out the entire cycle of the organisms in commercial yeast, and 

 thus clear up the question once and for ever. He, however, 

 started with the expectation of verifying the old pleomorphic theory 

 which would have made the Saccharomycetes a stage in the life- 

 history of some hyphal fungus, and whilst groping about in the 

 uncertainty in which this presumption had enveloped the subject, 

 alighted on the truth. 



His method of investigation was to cultivate a few cells, taken 

 at random from a mass of yeast, upon well cleaned thin slices of 

 potato or carrot, which were placed in a damp chamber, with 



* Etudes siir la Biere, Cap. iv. : — " . . . . Si Ton vient a le submerger de 

 fayon que I'oxygene de I'air arrive pbniblement en contact avec ses diverses parties 

 il decompose le sucre u la maniere de la leviire de bifere en formant du gaz acide 

 carbonique et de I'alcool." 



