CHAPTER XXXIX 



FUNGI IMPERFECTI 



Preliminary — Fungi imperfecti — Hyphales — Vuillemin's classification — Micro- 

 siphonales — Thallosporales — Hemisporales — Conidiosporales — Refer- 

 ences. 



PRELIMINARY. 



We now come to the last class of Schroeter's Eumycetes — -viz., the 

 Fungi Imperfecti ; that is to say, Eumycetes with a septate mycelium 

 and with spores which are not contained in asci or basidia, but are 

 carried on conidio spores, which may or may not be enclosed in 

 pycnidia. 



This class contains a large number of genera of importance in 

 tropical medicine, but everyone who has studied these fungi must 

 have felt, as we have, the great difficulty of determining to what 

 genus the organism belonged at which he was working. 



Various systems have been proposed, such as the mode of bearing 

 spores and the colour of the fungus, matters which change with 

 environment. Further septation of the spores often depends upon 

 their age and other factors. Similarly new species have been made 

 for a fungus, very like another fungus, but found on a new host. 

 In this way the classification has become almost hopeless. 



Vuillemin has, however, proposed a new classification, which 

 prevents the same fungus being variously classified in different 

 stages of its life-history. We adopt it for purposes of utility. 



CLASS: FUNGI IMPERFECTI Fuckel, 1869. 



Synonym. — -D enter omycetacece Saccardo (' Sylloge,' vol. xvi., 

 p. 825). 



Definition. — 'Fungi, almost invariably minute, in which asexual 

 reproduction takes place by means of conidia produced on conidio- 

 phores, which are either enclosed in perithecia, placed on discs, or 

 unprotected. 



Remarks. — Fuckel gathered together under the above name all 

 forms of fungi, the complete life-history of which was unknown, and 

 made this class in contradistinction to his other class of Fungi 

 Perfect!. Vuillemin, in 1910, suggested dividing the class into two 

 subclasses, D enter omycetes and Hyphales. 



Classification.— The Class Fungi Imperfecti may be subdivided 

 into two classes as follows : — ■ 



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