220 



rUXGI AND FUXGICIDES 



Like various other members of the family of rusts 

 to which this fungus belongs, it exists in three distinct 



FIG. 90. CLOVER RUST, 



c, Cluster-cups and secidium spores; d, uredo spores ;/, uredo pustule on clover 

 leaf; e, teleiito spores; fj, cross-section of stem showing mycelium between 

 cells; also two teleuto spores and one uredo spore. 



successive stages. Early in the season it appears — prin- 

 cipally upon white clover plants — in the so-called cecid- 



