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TEXT-BOOK OF FUNGI 



The conidia are produced singly or in chains, necklace- 

 like (concatenate), and are sometimes one-celled and 



FIG. 134. Helminthosporium echinulatum. i, portion of 

 a diseased carnation showing the pustules of fruit arranged in 

 concentric circles ; 2, small cluster of conidiophores bearing 

 the large, minutely warted, septate conidia, borne singly at 

 the tips of the conidiophores ; 3, a conidium that has ger- 

 minated in water : the germ-tubes bear short branchlets, each 

 of which produces a small, dark-coloured, secondary conidium 

 at its tip. Fig. i, nearly nat. size ; the remainder mag. 



minute, as in Coniosporium ; on the other hand, in Macro- 

 sporium, the conidia are comparatively very large and multi- 

 cellular. The genus Cercospora is parasitic on living leaves. 



