PRODUCED BY ALCOHOLIC FERMENTS. 219 



nature where the true Saccharomycetes multiply, and other 

 winter habitats than those mentioned, and which perhaps are 

 of greater importance. We are here, again, brought face to 

 face with the old question as to whether the Saccharomycetes 

 are independent organisms, or only forms of development of 

 the higher fungi. Should the latter prove to be the case, we 

 should naturally also have to take into consideration these 

 original forms, indeed it might even be possible that these 

 would prove of importance in clearing up the problem. These 

 purely theoretical investigations, regarded from this point 

 of view, thus become also of practical interest. Although 

 several of the most famous investigators have been at great 

 pains to discover these supposed progenitors, yet hitherto 

 no trace of them has been found. Recently attention has 

 again been drawn to this question, especially by Brefeld. 

 The position of the matter at the present time is such that 

 we must still regard the Saccharomycetes as independent 

 organisms.* 



From the foregoing investigations it is clear that, at all 

 times of the year, atmospheric dust may contain cells of true 

 Saccharomycetes, and amongst these disease yeasts. The soil 

 of fruit gardens offers the greatest danger in this respect. 

 The production of new generations of cells thus occurs in 

 nature at the time when the sweet succulent garden fruits 

 are ripe ; in Denmark this is especially the case in August 

 and September. In these months, therefore, the cells will not 

 only be most abundant in the dust particles, but they will also 

 be comparatively less enfeebled than at other times of the 

 year. The clouds of dust which are blown up from the soil 

 of fruit gardens in these months often contain an abundance 

 of young vigorous celts. 



My analyses of the micro-organisms of the air showed 

 that, in the year 1879, the Saccharomycetes gradually became 



* Addition 1895. For the present no decisive conclusion can be drawn from 

 Juhler's and Jorgensen's observations mentioned on page Si. 



