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RESEARCHES ON FUNGI 



course, they are shot away successively into the air. They fall 

 through the air, as represented diagrammatically in Fig. 119, and 

 settle on the surface of the malt -agar in the lower upright Petri-dish 



Fig. 119. — Tilletia tritici. The making of a new culture by the basidiospore-discharge 

 method. Vertical section through the apparatus employed : a, a malt-agar 

 plate (Petri dish) with mycelial mats at the surface of the agar, inverted over 

 a newly poured malt-agar plate b ; c, a bell-jar resting on a sheet of glass d. 

 The basidiospores are shot from sterigmata produced by the mycelium and, as 

 shown diagrammatically, fall through the air and settle on the sterilised agar in 

 the lower plate. The plate b is now sufficiently inoculated with basidiospores 

 and may be removed and covered with a sterilised Petri-dish cover. Falling 

 spores diagrammatically enlarged ; apparatus about three-quarters the natural 

 size. 



base. The fall of the basidiospores on to the new dish is allowed to 

 proceed for about three hours. At the end of this time, the old 

 inverted Petri-dish base is removed. The lower Petri-dish base is 

 then covered with its own cover (of which due care has been taken) 

 and set under a bell-jar. The basidiospores which fell on to the 



