MYCOLOGY DURING THE PAST FIFTY YEARS 579 



of the medical profession, but also various state boards of health and the 

 research staffs of some of the larger companies in the pharmaceutical industry. 

 From the early pioneer investigations showing that the heavy load of spores 

 of smuts and rusts of cereals released into the air from the thrashing opera- 

 tion on these grains could cause allergic reactions on the part of some people, 

 the work has extended to implicate a considerable number of fungi as respon- 

 sible exciting agents and has brought out some interesting differences such as 

 the generalized reaction to species of Alternaria and the strikingly specific 

 response to species of Cladosporium. Also, these agents have been found to 

 be active not only outdoors but also inside the home, where the sources of 

 the excitant spores have been traced in some cases to the filling of mattresses 

 and pillows and in others to damp cellars. 



Finally, the advances in Mycology during the past half century have in many 

 cases found expression in the applied fields. In Plant Pathology, where the 

 threat of some newly recognized and highly destructive fungus disease can al- 

 ways be counted upon to arise opportunely with stimulating effect, the menace 

 of chestnut blight, of the Dutch elm disease, and more recently of the oak 

 wilt have aroused renewed and eager activity and yielded helpful mycological 

 information on the nature, origin, distribution, and activities of the fungi 

 concerned. The stimulating contest between the development of new patho- 

 genic strains by such fungi as the smuts and rusts and wilts on the one side 

 and the plant breeder and plant pathologist on the other has yielded not only 

 strains of crop plants, hardier and more resistant to these diseases, but also 

 fundamental mycological information on the action of fungus parasites and 

 the mechanisms of susceptibility, tolerance, and immunity. Continued employ- 

 ment of the indispensable services of spores and other fungus material as the 

 means for testing the efficacy of fungicides and for determining the mechanisms 

 by which they function has yielded helpful information as to the effect on 

 fungus cells of chelating compounds, of cell toxicants, and of enzyme in- 

 hibitors. 



Also, there have been advances contributive to progress in the field of 

 mildew-proofing and the protection of textiles, of foodstuffs, of electronic 

 apparatus, and of other important materials and equipment against the in- 

 roads of destructive fungi. In the research and development laboratories of 

 the Quartermaster Corps and of other branches of the Armed Forces, as well 

 as in similar laboratories of pertinent industries, there has been productive 

 continuation of the investigations stimulated and instigated by the imperative 

 urgency of the severe losses occasioned by the destructive activity of fungi 

 under drastic tropical conditions during the last war. The original programs 

 set up to determine what organisms were concerned in this deterioration, how 

 they operated and how they might be controlled, have led to two lines of 

 development. They have set in motion fundamental studies on the break- 

 down of cellulose and other raw materials, as already noted previously. Also, 



