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CLASSIFICATION OF THE MICRO-ORGANISMS. 



Different 

 modes of 

 spore form- 

 ation in the 

 same fungus. 



oospores are the forms which usually behave as resting 

 spores. 



These different kinds of fructifying organs occur at 

 times together or in succession on one and the same 

 thallus ; the same fungus can under certain conditions 

 furnish hasidiospores, and under other conditions asco- 

 spores ; thus there is frequently a polymorphism of the 

 fructifying organs. In addition an alternation of genera- 

 tion often occurs ; the thallus of one fungus bears only 

 one form of fructifying organ ; the spores so developed 

 grow to form a thallus whicfris different from the original 

 thallus and gives rise to another fructification, often 

 indeed not growing on the same host, but requiring 

 another species of plant for its development. From the 

 spores formed on the second thallus, the original my- 

 celium with its characteristic fructification is again 

 developed. 



Sketch of the 

 classification 

 of the fungi. 



Classification of the True Fungi. 

 (After Frank in Leuriis's Synopsis). 



First order : Ascomycetes. Highly developed form of 

 fungus ; at the height of vegetation ascospores are 

 formed. A formation of prot ospores often precedes this 

 fructification, these bodies appearing in the form of 

 conidia-carriers and conidia or spermogonia. The 

 protospore forms of the ascomycetes, such as Eurotium 

 aspergillus, Erysiphe oidium, &c., which occur much 

 oftener in nature than the higher forms of fructification, 

 were formerly described as particular species of fungi, 

 and have only recently been associated with the ascospore 

 forms. 



Families : PerisporiaceaB, Pyrenomycetes, Tuberaceae, 

 Discomycetes, Gymnoasci. 



Second order: Basidiosporece. In these the spore 

 formation always occurs by acrogenous segmentation, 

 even when the fungi have reached the acme of develop- 

 ment. Almost all form fructifying bodies, which carry 

 in their interior a hymenium layer of basidia. 



