

421 



CHAPTEK II. 



PROTECTION AGAINST FUNGI. 

 SECTION I. GENERAL ACCOUNT.* 



1. Position of Fungi in the Vegetable World. 



PLANTS belonging to the lowest division of cryptogamous 

 plants which is termed Thallophyta, and includes among 

 other families bacteria B>nd fungi have at most only rudimen- 

 tary differentiation into stems, leaves, and roots ; and consist 

 of cellular tissue, which may, however, in certain cases become 

 hardened. 



Bacteria termed also Schizomycetes, or fission-fungi, from 

 their habit of constantly dividing to form new cells, are plants 

 consisting of cells the diameters of which are usually consider- 

 ably less than ^ j n of a millimetre. They are parasitic or 

 saprophytic on organic substances, and under certain condi- 

 tions may multiply enormously in the blood or digestive organs 

 of men or animals, and cause highly infectious diseases such 

 as cholera, malaria, typhoid fever, etc. 



Marshall Ward has published some papers in the " Pro- 

 ceedings of the Eoyal Society" proving that sunlight is preju- 

 dicial to the growth of bacteria, which cannot therefore thrive 

 on or in the young sub-aerial organs of forest plants ; certain 

 bacteria, however, according to Hartig, cause bulbs and potato 

 tubers to rofc, yet he states that the only disease in European 



* Cf. "A Text-hook of Plant-diseases caused by Cryptogam ic Parasites, "by G- 

 Massee. London : Duckworth & Co., 1903. 



"Fungoid Pests on Cultivated Plants," by M. C. Cooke. London: Spottis- 

 woode & Co., 1906. 



Von Tubeuf, Dr. Karl, " Pflanzenkrankheiten durch kryptogame Parasiten 

 verursacht." Berlin, 1895. English translation by W. Smith. Longmans, 

 London, 1899. 



Hartig, R., " Lehrbuch der Baumkrankheiten." Berlin, 1889. English trans- 

 lation of earlier edition of above by Somerville and Marshall Ward. Macmillan 

 & Co., London, 1894. 



Nisbet, " The Forester." Blackwood & Sons, 1905. Vol. II., pp. 141187. 



