CHAPTER I 



THE PHENOMENA OF SPORE-DISCHARGE 



Upon the Identity of the Phenomena of Spore-discharge in the Hymen omycetes 

 and the Uredineae — The Discharge of Basidiospores in Pnccinia graminis — 

 The Discharge of Basidiospores in Endophyllurn, Euphorbiae-sylvaticae — The 

 Discharge of Basidiospores in Gymnosporangium Juniperi-virginianae — Models 

 of Basidia 



Upon the Identity of the Phenomena of Spore-discharge in the 

 Hymenomycetes and the Uredineae. — After Tulasne had dis- 

 covered that the teleutospores of the Uredineae, on germination, 

 produce a septate promyceHum bearing four sporidia, and that the 

 basidium in the TremelHneae is septate, it became obvious that 

 the promyceHum of the Uredineae is homologous with the septate 

 basidium of the TremelHneae and with the non-septate basidium 

 of the Hymenomycetes and Gastromycetes ; ^ and de Bary, who 

 accepted the doctrine of evolution, expressed the view that the 

 Uredineae, the TremelHneae, and the Hymenomycetes form a pro- 

 gressive phylogenetic series.^ 



The spore-bearing structure which is emitted by the teleuto- 

 spore of a Rust fungus was called a promycelium by Tulasne and a 

 protobasidium by Brefeld, In what follows we shall simply refer 

 to it as a basidium which produces sterigmata and spores. 



The view that the basidium is homologous in the Uredineae 

 and Hymenomycetes was based in the first place on evidence of a 



^ L. R. et C. Tulasne, " Memoire sur les Ustilaginees compar6es aux Uredinees," 

 Ann. sci. nat., 3 ser., T. VII, 1847, pp. 12-127 ; " Seconde Memoire," 4 ser., T. II, 

 1854, pp. 77-196 ; L. R. Tulasne, " Observations sur I'organisation des Tremellinees," 

 3 ser., T. XIX, 1853, pp. 193-231. 



^ A. de Bary, " Untersuchungen iiber die Peronosporeen und Saprolegnieen und 

 die Grundlagen eines natiirlichen Systems der Pilze," Beitrdge zur Morph. u. Phys. 

 der Pilze, Frankfurt a.M., 1881, p. 131, etc. 



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