. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. 526 ALTERATION OF FORM BY PARASITIC FUNGI. farther apart than in the healthy plant on account of this stretching of the stem. The lower leaves of the shoot are transformed into small fringed scales, and the upper ones are so much shortened that their outline becomes almost circular. The second parasite to which the Cowberry shoot is subject is Exobasidium Vaceinu (a near ally of the already mentioned Exobasidium Lauri, p. 521). The stem becomes pale rose-red colour, and rather thickened and spongy, b
. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. 526 ALTERATION OF FORM BY PARASITIC FUNGI. farther apart than in the healthy plant on account of this stretching of the stem. The lower leaves of the shoot are transformed into small fringed scales, and the upper ones are so much shortened that their outline becomes almost circular. The second parasite to which the Cowberry shoot is subject is Exobasidium Vaceinu (a near ally of the already mentioned Exobasidium Lauri, p. 521). The stem becomes pale rose-red colour, and rather thickened and spongy, but it does not elongate much more than usual; the leaves become blistered and curiously convex on the. Pig. 359.—A "Witches Bxotm un the Siher Fir, produced by ^tidiiati daUnum under surface. The substance of the infected leaves becomes brittle and loses its chlorophyll. A red tint appears in place of the green, especially on the upper surface of the leaf, whilst the lower surface, on which the spores develop, looks as if it had been dusted over with flour. Usually the buds develop prematurely on these shoots, the buds which, under ordinary circumstances, would not develop until the next year push out and form new shoots shortly after they have been laid down. The axes of these shoots, however, remain short; their leaves are closely crowded, red in colour, and sessile. From a distance the premature shoots look like large double red flowers inserted in the dark green of the non-infected Cowberry bush. The shoots which develop prematurely on the shrubs of the Bog Whortleberry (Vaccinium uliginosum) by the action of Exobasidium Vaccinii are often met with in alpine regions, and are even more noticeable on account of their fiery-red. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Kerner von Marilaun
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1895
