86 



MANUAL OF BOTANY 



forms where two kinds of gametophyte are met with. The 

 fungus producing Ergot {Claviceps) is an example of this. The 

 first form consists of a feltworli of mycehum, fiUing the ovary 

 of the Eye or Wheat plant, and giving rise by abstriction to 



Fig. 843. 



riff. 843. Young sclerotium, c, of Claviceps growing up and supplanting the 



old sphaoelia, sph. Fig. 844. Section throngli the junction of the 



sphacelia with the sclerotium ol Claviceps, showing formaticn o£ gonidia. 



Fig. 845. 



Fig. 846. 



Fig.^i. Portion of the horu-shaped sclerotium of Clai)icepspm-jmrea,oxttie 



JSrgot Fungus, bearing four stromata. Fig. 846. Longitudinal section of 



a stroma, magnified, showing the perithecia. After Tulasne. 



numbers of gonidia [fig. 844). This form is known as the 

 Sphacelia. Later in the year the mycelium becomes very dense 

 and hard, and protrudes from the ear as a black elongated body 

 which is known as a. sclerotium [fig. 843). After a period of rest 

 extending through the winter, the sclerotimn germinates, putting 



