TILLETIA TRITICI 209 



interior of a stinking smut-ball and thus, for the first time, demon- 

 strated their fungous nature. He observed and illustrated what 

 afterwards came to be known as the chlamydospores, the pro- 

 mycelium, the primary conidium, and the secondary conidium. 



Prevost held the view that the Stinking Smut disease is caused 

 by the Stinking Smut fungus, which he believed entered healthy 

 wheat seedlings from without ; but his attempt to perceive the 

 fungus forcing its way into the host-plant failed. However, the 

 correctness of Prevost's ideas about infection was subsequently 

 demonstrated by Kiihn and Wolff who saw the hyphae of the 

 parasite penetrating through the epidermis of the coleophyllum or 

 first leaf-sheath. 1 



In 1847, Tulasne 2 reinvestigated the germinations of the 

 chlamydospores of the Stinking Smut fungus and confirmed Prevost's 

 observations. Tulasne's further work upon Rust fungi, Tremelli- 

 neae, and other Basidiomycetes led to the view, adopted by Brefeld 

 and others, that the promycelium and primary sporidia of the Smut 

 and Rust fungi are homologous with the basidia and basidiospores 

 of the Tremellineae, the Hymenomycetes, and the Gastromycetes. 



In recent years, investigations upon the Uredineae, 3 the Hymeno- 

 mycetes 4 and the basidiomycetous yeast-genus Sporobolomyces 5 

 have shown, in all these fungi, that : (1) a basidiospore is always 

 developed asymmetrically on the end of a conical sterigma ; (2) the 

 spore-hilum is situated at the top of the sterigma ; (3) a few seconds 

 before spore-discharge, a drop of liquid is excreted at the spore- 

 hilum ; (4) violent spore-discharge takes place ; and (5), on 



1 Cited from Woolman and Humphrey, loc. cit., p. 7. 



2 L. R.and C. Tulasne, "Memoire sur lesUstilagineescompareesauxUredinees," 

 Ann. Sci. Nat. Bot., 3 ser., T. VII, 1847, pp. 12-127 ; Seconde Memoire, 4 ser., T. II, 

 1854, pp. 77-196 ; L. R. Tulasne, " Observations sur l'organisation des Tr£mel- 

 linees," ibid., 3 s<§r., T. XIX, 1853, pp. 193-231. 



3 P. Dietel, " Uber die Abschleuderung der Sporidien bei den Uredineen," 

 Mycologisches Centralblatt, Bd. I, 1912, pp. 355-359; and A. H. R. Buller, Researches 

 on Fungi, Vol. II, 1922, pp. 168-169 ; Vol. Ill, 1924, pp. 498-519, 533-537. 



4 A. H. R. Buller, Researches on Fungi, London, Vol. II, 1922, pp. 4-20. 



5 A. J. Kluyver and C. B. van Niel, " Uber Spiegelbilder erzeugende Hefenarten 

 und die neue Hefengattung Sporobolomyces," Centralb. f. Bakteriologie, Abt. 2, 

 Bd. LXIII, 1924-1925, pp. 1-20, Taf . I and II. Also A. H. R. Buller, in this volume 

 of Researches, pp. 181-183. 



vol. v. r 



