. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. FUNGUS-GALLS ON STEMS. 521 colour takes its place, so that orange spots appear on the surface of the foliage, contrasting vividly with the green of the unaltered portions of the leaf. Galls rising from sharply defined parts of the stem are comparatively rare. One of the most remarkable is produced on the stems of a Laurel (Laurus Canariensis) by the parasitic Exobasidium Lauri. When it appears above the bark it looks like an aerial root, but rapidly grows into a branched spongy body 8-12 cm. long sim
. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. FUNGUS-GALLS ON STEMS. 521 colour takes its place, so that orange spots appear on the surface of the foliage, contrasting vividly with the green of the unaltered portions of the leaf. Galls rising from sharply defined parts of the stem are comparatively rare. One of the most remarkable is produced on the stems of a Laurel (Laurus Canariensis) by the parasitic Exobasidium Lauri. When it appears above the bark it looks like an aerial root, but rapidly grows into a branched spongy body 8-12 cm. long similar in appearance to one of the Fungi belonging to the family Clavariese (c/. fig. 195^, p. 21). The galls produced by Entyloma Aschersonii and Magnusii on the Composites Helichrysum arenarium, and Gnaphaliuvi luteo-albv/m. Fig. 357.—rungus-galls. 1 Gall on the stem of the Juniper (Juniperus communis) produced by Gymnosporangium clavctriaiforme. 2 (jall on the leaves of Aronia rotundifolia produced by Gymnospora/ngium conicum. take the form of outgrowths, varying from the size of a pea to that of a walnut, developed from special spots on the root. Whether the spherical tubercles growing on the root-fibres of many Leguminosse, especially those of the Bird's-foot Trefoil (Lotus corniculatus), the Fenugreek (Trigonella fcemrni-grcecum), Lady's-Fingers (Anthyllis Vulneraria), Lupin (Lupinus variabilis), and the Liquorice (Glycyrrhiza glabra) are to be regarded as true galls caused by the Bacteria-like organisms invariably to be found in their interior is questionable. According to the most recent investigations they are the outward expression of a case of symbiosis and not of pure parasitism. Gall developments which involve whole roots or rootlets are found on the Alder (Alnus glutinosa), and on the Cabbage XBrasaica oleracea). The gall which is produced on Alder roots by Frankia Alni attains the size of a walnut and has a. Please note that these images are extracted from scanne
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1895
