io8 TEXT-BOOK OF FUNGI 



I have frequently observed that from the broken ends 

 of conidiophores of Cladosporium, Helminthosporium, and 

 other moulds, when present in a hanging-drop culture, 

 a new growth started which developed into a branch bear- 

 ing a head of concatenate conidia, smaller and different 

 in other respects from the normal conidia of the species 

 under observation. 



Brefeld, Unters. Gesammt. MykoL, Heft 8 (1889). 



Biffen,y^^r. Linn. Soc., 34, p. 14 (1898). 



De Bary, Fungi Mycetozoa and Bacteria (Engl. ed.), 

 p. 30 (1887). 



Hartig, Wichtige Krank. d. Waldbaume, 1874. 



Haberlandt, an account of mycorrhiza in tropical countries, 

 Eine botanische Tropenreise, Leipzig, 1893. 



LIBERATION OF SPORES AND CONIDIA. 



In those groups of the Phycomycetes, as the Sapro- 

 legniaceae, Chytrideae, and Peronosporeae, where aquatic 

 zoospores are formed, a specialised portion of the wall of the 

 zoosporangium, usually situated at its apex, becomes soluble 

 in water when the zoospores are ready for liberation. At 

 this period water is absorbed, and a hyaline layer lining the 

 wall commences to swell ; as the wall of the zoosporangium 

 is comparatively rigid, the swollen contents expel the 

 zoospores, through the specialised apical opening, into the 

 surrounding water. 



In most members of the Mucorineae the upper portion 

 of the sporangial wall, which is usually coated externally 

 with a thin coating formed of minute particles of oxalate 

 of lime, becomes soluble in water at maturity, and the 



