CHANGE IN APPROACH TO STUDY OF FUNGI 9 



related to the rust on wheat, that the hyphae in wood are the 

 assimilatory stage of the conks which form at the surface of 

 standing trees or logs, that Flasmodiophora brassicae causes club 

 root of crucifers, and that different cereal smuts accomplish in- 

 fection at definite critical periods only. This type of research 

 stimulated an appreciation of the economic importance of fungi 

 and led to wide interest in applied mycology and plant pathology. 

 A summary of this work is contained in Whetzel's History of 

 Phytopathology (1918). 



As an outgrowth of the establishment of the fact that mi- 

 crobes cause fermentations came Hansen's researches on the mor- 

 phology and physiology of yeasts and the assemblage of studies 

 on the industrial' usage of fungi in Lafar's Technische Mykologie 

 (1904-1907). This phase of mycologic interest, in its recent 

 developments, is more fully discussed in Chapter 4, Volume II, 

 where its results are briefly summarized. 



'Change in approach to study of fungi. Gross morphologic 

 similarities and differences constituted the bases for groupings in 

 the early attempts to classify fungi. Then, as microscopes came 

 into use as aids in elucidating details of structure, more and more 

 attention was devoted to microscopic features. Characteristic 

 structural features found by examination with the microscope 

 were employed increasingly to supplement those observable by 

 the unaided eye, but for a long time the purpose of such studies, 

 as the numerous monographs that have appeared indicate, w^as 

 purely taxonomic and classificatory. Gradually there came into 

 being an appreciation of detailed structure and a grasp of its im- 

 portance, as portrayed in Bulliard's Champignons de France and 

 the Tulasnes' Selecta Fimgonim Carpologia. This new point of 

 interest eventually resulted in de Bary's Morphologic imd Physio- 

 logic der Pilze, Flechten, iind Myxomyceten (1866), which my- 

 cologists everywhere regard as a basic w^ork in the study of 

 fungi. In it developmental morphology is emphasized, and the 

 taxonomic approach may with fairness be said to be deempha- 

 sized. At any rate, the investigations by de Bary and similar stud- 

 ies by his students have securely established the morphologic 

 approach to mycologic knowledge, ^^^here the primary interest 

 remains to this day. In fact, de Bary is universally conceded to 

 be the father of modern mycology. 



