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TEXT-BOOK OF FUNGI 



sterigma retains its parietal protoplasm after the spore is 

 cut off, and its elastic wall continues to stretch as the 

 tension due to the accumulation of water increases. 

 When the tension reaches a certain point, the wall of the 



FIG. 37. Sclerotinia urnula, a Discomycete, the 

 conidia of which are liberated by ' dis junctors.' i, chain 

 of conidia in a young stage; 2, chain of conidia at 

 maturity, the narrow necks or disjunctors deliquesce 

 and liberate the conidia ; 3, ascophores springing from 

 mummified berries of Vaccinium filled with mycelium, 

 forming a sclerotium ; 4, ascus containing eight spores ; 

 5, paraphyses. Fig 3, nat. size; the remainder highly 

 mag. 



sterigma ruptures in a circular manner just below the 

 septum at its apex; the elastic wall of the sterigma in- 

 stantly contracts and forces its contained water to strike 

 the apical transverse wall, which is thus thrown off along 

 with the spore seated upon it. 



