504 



FUNGI IMPKRFECTI. 



Mastigosporium. 



Conidia hyaline and four-celled, frequently bristled. 



Mastigosporium album Riess. produces oblong dark spots 

 with light margins on leaves of living grass. The conidia 

 are produced on the margins of the spots (Fig. 308). 



Fusoma. 



Similar to Fusarium, but the mycelium is loose and not 

 aggregated into a tuft. Conidia spindle-shaped and septate. 



Fig. 300. — Fusoma parasiticum. Dis- 

 eased Pine-seedlings, with, a, root killed ; 

 li, hypocotyl killed ; c, first leaves and 

 plunmle killed. (After R. Hartig.) 



Fig. 310. — Epidermis of a Pine-seedling 

 with a stoma. Some hyphae of Fusoma 

 have produced partial dissolution of cell- 

 walls. (After R. Hartig.) 



Fio. 311.— Fusoma parasiticum. Coni- 

 dia— immature, mature, and germinat- 

 ing. (After R. Hartig.) 



Fusoma parasiticum Tub.^ is the cause of a disease of seed- 

 lings, particularly those of Conifers. The first symptoms are 

 dark patches on the seedlings, followed by their collapse. There- 



' E, Hartig, For.stlich-naturwis.s. ZeitschH/t, 1S98, p. 4:«. 



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