DISEASES. 181 



" The extensive prevalence of the cholera, over large 

 portions of the globe, commencing in the year 1818, led 

 medical men to seek for its cause. Dr. Cowdell, of Lon- 

 don, in 1848, published 'A Disquisition on Pestilential 

 Cholera, being an attempt to explain Hs phenomena, na- 

 ture, cause, prevention and treatment, by reference to an 

 extrinsic fungous origin.' 



"In 1849, Prof. J. K. Mitchell, of Philadelphia, issued 

 a more elaborate work, * On the Oyptogamous Origin of 

 Malarious and Epidemic Fevers.' Jt abounds in numerous 

 facts and correct reasoning, and should be consulted by 

 every investigator of disease, animal and vegetable. 



u These publications attracted the attention of the med- 

 ical profession, both in America and Europe, so long as 

 that epidemic continued its ravages, and the theories they 

 advanced gained extensive credence during that time. 

 They were, however, lost sight of when that epidemic 

 subsided. Recently they have been substantiated as plain 

 matters of fact, so far as malarious diseases are concerned, 

 by the labors and investigations of Prof. J. H. Salisbury, 

 of Cleveland. 



" It is well established, then, that a number of diseases 

 of the animal system are produced by fungi. ' Under this 

 name botanists comprehend not only the various races of 

 mushrooms, toadstools, and similar productions, but a 

 large number of microscopic plants, forming the appear- 

 ances called mouldiness, mildew, smut, rust, brand, dry 

 rot, etc.' They are universally diffused in nature. It is 

 difficult to conceive of a place where they do not exist. 

 They are among the most numerous of all plants, in re- 

 gard to genera and species, and with very few exceptions 



