nSTJLAQINEuS. 



321 



there grow out small sporidia, which germinate by sending 

 out a slender hypha ; when this hypha comes in contact 

 with the proper host plant, it penetrates the walls of its 



Fig. 234.— M/Mia cmies. d, transverse section of an infected wheat-grain ; e, ripe 

 spore ; /, the first stage of germination ; g, the formation of a branching promyce- 

 iium, witti granular protoplasm in its upper end ; A, the formation of slender 

 branches which unite by a lilrid of conjugation ; the ends of these branches give rise 

 somewhat later tcf very small sporidia, and when thete germinate very sleudt r hy- 

 phse are produced, which peueirate the epidermis as at i ; f , mycelium from the 

 young ovary of the wheat— two small lateral branches are shown, from which spores 

 will develop ; k, spores more fully developed.— <?, after GErsted ; e-A, after Tulasne, 

 X 460 ; i-zfe, after Kuhn, X 300. 



cells, and thus gains admittance to its interior, where it pro- 

 duces a new mycelium* (Fig. 234, i). In Ustilago carlo the 



* This is upon the authority of Kulin : " Krankheiten der Culturge- 

 wachse," 1859. There are some doubts as to the correctness of his 

 pheervations, and they have not been confirmed by any one, 



