Fig. 3. Germination of onion smut spores. A. A fresh spore before germination. B - Q. Succes- 

 sively older stages of germination of spores three months after maturity. Camera lucida drawings. 

 R-U. Successive stages in the germination of spores after ripened in soil for three years. 1 hoto- 

 micrographs. 



