PREFACE 



The object of this volume is to make contributions to our knowledge 

 of certain Phycomycetes, Ascomycetes, and Basidiomycetes. 



Part I is devoted to a study of Pilobolus. The ocellus function 

 of the subsporangial swelling has been treated of in detail. A new 

 species of Pilobolus has been described, and a final Chapter on the 

 Systematics of the Pilobolidae has been contributed by my friend, 

 Mr. W. B. Grove. 



Part II is concerned with the production and liberation of spores 

 in the Discomycetes. The phenomenon of puffing has been discussed ; 

 and attention has been called to the fact that the asci of many 

 Discomycetes are heliotropic, so that light is of great importance 

 in directing the ascus guns toward the mouths of cup-shaped 

 fruit-bodies and toward the openings of the hymenial depressions 

 in Morchellae. Finally, a simple method for making audible the 

 puffing of Discomycetes has been described. 



The first two Chapters of Part III treat of the pseudorhizae of 

 Collybia radicata, C. fusipes, Coprinus macrorhizus , and other 

 Hymenomycetes, while the final Chapter treats of Omphalia flavida 

 as a luminous and gemmiferous Coffee leaf-spot fungus. The 

 gemmae of this fungus are unique, for they appear to have been 

 derived from pilei which have become sterile and detachable. With 

 a view to enabling the reader to compare the gemmifers of 0. flavida 

 with those of Sderotium coffeicola (another Coffee leaf-spot fungus), 

 a brief account of S. coffeicola based in the main on Stahel's 

 investigations has been appended. 



This volume contains two hundred and thirty-one illustrations 



vii 



