Fungi, Ascomycetes, Ustilaginales, Uredinales . its wall is variously roughened in most speciesby minute projections on the surface. Two or more germ-pores are usuallypresent and the uredospore, like the cells which give rise to it, is invariablybinucleate ; it produces a binucleate mycelium on which teleutospores orfurther crops of uredospores are formed. Certain species(Puccinia vexans,etc),occurring under very dry conditions, \ lit I LRKDINALKS 205 produce a second type of uredospore with thick walls which arc adapted tosurvive unfavourable conditions; these are known as amphispores. Both a
Fungi, Ascomycetes, Ustilaginales, Uredinales . its wall is variously roughened in most speciesby minute projections on the surface. Two or more germ-pores are usuallypresent and the uredospore, like the cells which give rise to it, is invariablybinucleate ; it produces a binucleate mycelium on which teleutospores orfurther crops of uredospores are formed. Certain species(Puccinia vexans,etc),occurring under very dry conditions, \ lit I LRKDINALKS 205 produce a second type of uredospore with thick walls which arc adapted tosurvive unfavourable conditions; these are known as amphispores. Both aecidio- and uredospores germinate readily and without a rest iffully ripe, but many are shaken off by wind and rain before they reachmaturity and remain incapable of germination. Moreover it is stated thatspores will not ripen properly on leaves that have been removed from theplant. Sooner or later the mycelium of binucleate cells gives rise to teleuto-spores; these are characteristically grouped together in teleutosori (fig. 180), w-*—^^/-.
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
