30 TEXT-BOOK OF FUNGI 



elasticity of the cell-wall and turgidity in unicellular forms, 

 whereas in multicellular species there are such factors as 



FIG. 6. Tilletia tritici, a fungus showing 

 secondary spores fusing in pairs, i, ear of wheat 

 attacked by the fungus ; 2, a spore ; 3, 4, spores 

 germinating and producing a germ-tube bear- 

 ing a cluster of secondary spores at the tip ; 5, 

 two secondary spores that have conjugated or 

 joined by a transverse outgrowth ; one of the 

 secondary spores has produced a sporidiolum. 

 All, except fig. i, mag. 



transverse septa, thickening of the cell-walls, and in some 

 of the higher forms of Polyporus there is a specialised 



