APPENDIX I. 



YEASTS AND MOULDS. 



Yeast- fungi and mould-fungi, like bacteria or fosion-fungi, are- 

 achlorophyllous Thallophytes. They belong to two separate orders 

 the Saccharomycetes and Uyphomycetes which are intimately related 

 to each other, but quite distinct from bacteria. Their germs occur 

 widely distributed in air, soil and water, and are constant I v 

 encountered in bacteriological investigations. In addition, many 

 species are of hygienic and pathological interest and importance in 

 being either accidentally associated with, or the cause <>f \ 

 morbid processes and fermentations. For a complete account of 

 all the described species and full details of the various form- <>t 

 development, reference must be made to botanical and oth-i 

 works.* A description of certain species is appended here, an 

 afford some useful information to the worker in a bacteriological 

 laboratory. 



YEAST-FUNGI OR SACCII.MSM.MY* i:n>. 



Saccharomyces cerevisise (Tonda cere/v.s/</).- ' 

 oval, 8 to 9 /A long, singly or united in Mn.-ill dud Sj,.,!-.^ 



occur three or four together in a mother- c 11. I t. '> // in diam. 

 S. cerevisi*, S. pastorianus and S. ellip>oi 1,-ns an- ;n-tiv ftk 

 ferments. According to Jorgensen they will produce in fourteen 

 days in beer-wort from 4 to 6 per cent., by volume, of alc-h-.l. 



Saccharomyces ellipsoideus (Il.m-n). I. Klliptira: 

 mostly 6 ^ long, singly or unit.-l in littl- br 

 four spores found in a mother-cell, 3 to 3'5 p in diam. 

 on the surface of wort -gelatine th-y pro,lu<-- i" etovn to fourteen 

 days, at 25 C., a net-like growth l.y wl.irh they can be recogDiBed 



* Sachs, Text-book of Botany ; Jorgensen, Micr*-0rgariim* and Fermen- 

 tation. 



