INTRODUCTION. 



The investigations on smut fungi diseases, published in Parts V, XI and XIP of this work, 

 date back, in their beginning, to the second half of the 70's in the last century. It was a time 

 when a noticeable standstill had come in the investigations of smuts and smut diseases. More 

 than 25 years had already elapsed since Tulasiic'- had carried through methodically the germina- 

 tion of smut spores in water and had ascertained that these spores did not germinate into 

 niycelia, but into short germinating tubes which, becoming fructificative with an early cessa- 

 tion of their growth, form conidia. Tulasne designated this fructificative kind of spore germi- 

 nation as germination with promycelia and spo ridia. He had observed also an almost corre^ 

 spending fructificative germination in the tale'ntospores of Uredo and had used here too the; 

 same designation by which he had already expressed hypothetically the close connection of both 

 form of fungi. 



Meanwhile experimental infection had been carried out with smut spores whose peculiar 

 germination had now 1)cen ascertained by Tulasne, m order to develop smut diseases in the differ- 

 ent proper host plants. These experiments were made chiefly by /. Kuhn''^ and showed that the 

 mature plants are resistent to and insured against the attacks of smut germination and that infec- 

 tion remains limited to the short stage of the germination of the seed. Disinfection with solutions 

 of copper sulfate, previously carried out with success, — thus killing the smut spores.^-obtained 

 here its natural explanation and valuation^. The germinating seedlings are attacked in the earth 

 by the germs of infection which come in contact witli them. They penetrate quickly through the 

 young tissues into the meristematic tissue of the seedling and continue their growth here, in order 

 to form later the smutted places on the completely matured plants, usually in their ovaries. 

 The place on which the smut appears on the plants attacked lies accordingly as far distant 

 as possible from the place of infection in the young seed. During the period of development of 

 the host plants, nothing may be seen of the effect of the infection. The accommodation of the 

 parasites to their hosts is thus absolutely complete. The parasite appears externally only in the 

 last stage of development. 



(1) Botanische Untersuchungen iiber Hefenpilze. Untersuchungen aus dem Gesammtgebiete der 

 Mycologie. V. Heft. Die Brandpilze I. Verlag von ARTHUR FELIX, Leipzig, 1883. Band XL Die Brand- 

 pilze H. Die BrandkranUheiten des Getreides. Commissionsverlag von HEINRICH SCHONINGH. Munster, 

 1895. — XIL Heft. Hemibasidii, Brandpilze III. Commisslons-verlag. Mun,ster i. W. 1895. 



(2) TULASNE, Mfemoire sur les Ustilagin6es comparges aux Ur^d. Ann. d. Sc. nat. 3 Sferie Tome 7, 

 1847 — Seconde Mfemoire s. 1. UrSdin^es et les Ustilag. Ann. d. sc. nat. 4 S6rie, Tome 2, 1854. As is well 

 Itnown, PREVOST before TULASNE had observed the germination of smut spores in water and from 

 this had traced smut diseases to fungi living parasitically. 



(3) KUHN, Die Krankheiten der Kulturgewachse. Berlin, 1858, and later works. 



(4) The fungicide action of copper on smut spores has also been stated by PREVOST. 



