UNCINULA 



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that the ascigerous fruit was first met with on grapes, both 

 growing under glass and out of doors. This discovery 



Fig. 39. Uncinnla spiralis. 1, fungus forming white mildew- 

 patches on upper surface of vine leaf; 2, portion of vine leaf 

 with fungus bearing perithecia ; 3, mycelium bearing erect 

 chains oi conidia, a, a, and haustoria which enter the cells and 

 absorb food, b, b 4, a single conidium ; 5, a perithecium with 

 its curled appendages ; 6, an ascus containing six spores ; 7, a 

 free ascospore ; 8, grapes attacked by the fungus. Figs. 1 and 

 2 somewhat reduced ; the rest highly mag. 



showed the fungus to be Uncinnla spiralis, Berk, and Curt. 

 ty=Uncinula necator, Burr.). This fungus is undoubtedly of 



