. Botany for high schools and colleges. Botany. i/HhWlNEu^. 315. Fig. 219.âYonnz teleute- sporcB of Phraginidium m/Ur- cvonatum, showing tlie an- gular maeees which eventu- ally develop into the cells ture follow or proceed from a sexual act; and maintains that the secid- ium fruit is more complex in structure than any of llie oiliers. He further says, " The Eecidium fruit corresponds, then, to the perithecium of the Ascomycetes, tlie secidiospores to the ascospores; and the uredo- spores and teleutospores are evidently differ- ent forms of ; It is very doubtful, however, whe
. Botany for high schools and colleges. Botany. i/HhWlNEu^. 315. Fig. 219.âYonnz teleute- sporcB of Phraginidium m/Ur- cvonatum, showing tlie an- gular maeees which eventu- ally develop into the cells ture follow or proceed from a sexual act; and maintains that the secid- ium fruit is more complex in structure than any of llie oiliers. He further says, " The Eecidium fruit corresponds, then, to the perithecium of the Ascomycetes, tlie secidiospores to the ascospores; and the uredo- spores and teleutospores are evidently differ- ent forms of ; It is very doubtful, however, whether future investigations will prove the correctness of Sachs' surmise. It is much more probable that the teleutospores re- sult from a sexual act, and that they are to be compared to the asci of the Ascomycetes. The teleutospores are possibly reduced asci, containing one or more large ascospores; in some casesâ'., in Puccinia Helianthiâan outer investing membrane can be distinguisli- ed after treatment â vvith potassic hydrate, while in Puccinia (Uropyxis) Amorphm there of'the mature teleutospore. is " a deciduous outer coat,"* which contains ° y^^S"" ^ ⢠the double spore, and (when moistened) a mass of jelly. In both these cases the membranous covering closely resembles an ascus which fits closely over its contained double spore. In the genus Phragmidium (Fig. 220), especially in young teleutospores, the resemblance to asci and ascospores is still more striking; the so- called " cells" of the teleutospore originate as so many separate masses in the interior of a large ascus-like membrane (Fig 219); in their further development the cells become large, and at last fill up the whole cavity, and then have the ap- pearance of Fig. 330. Tlie resemblance of the teleutospores to re- duced asci is close enough to make it probable that sexual organs resembling those of Asco- mycetes will be found to precede them. This is rendered the more pro
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1885
