. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. 166 ASt'OMYCKTES. This is supported by Smith's investigations, in which an an- atomical comparison of diseased twigs of peach and ahuoiid showed no difference in the pathological effects. Exoascus crataegi Fuck, occurs on Crataegus Oxyavantha, and causes red swellings on the leaves and flowers, accom- panied l)y hypertrophy of shoots in which the mycelium perennates. Exoascus Tosquinetii (West.). The deformation cause
. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. 166 ASt'OMYCKTES. This is supported by Smith's investigations, in which an an- atomical comparison of diseased twigs of peach and ahuoiid showed no difference in the pathological effects. Exoascus crataegi Fuck, occurs on Crataegus Oxyavantha, and causes red swellings on the leaves and flowers, accom- panied l)y hypertrophy of shoots in which the mycelium perennates. Exoascus Tosquinetii (West.). The deformation caused by this species is frequent on the black alder ( glutinosa). The thickened, elongated, wrinkled twigs render attacked parts very conspicuous in contrast to the normally developed parts of the tree. The leaves may l)e wholly attacked and much enlarged, or they may only be hypertrophied at places so as to form pustule-like swell- ings. The epidermal ami mesophyll-cells of diseased leaves become greatly en- larged. Exoascus aureus (Pers.). The leaves of the black poplar (Pojn'/vs iiigra) attacked by this parasite exhibit pustides (Fig. 62). The asci are formed as a golden coating fin the concave side of the ])ustules, which is, in most cases, the under side of the leaf, rarely the upper. The cells forming the pustules have thicker walls and a somewhat different shape from the normal epidermal cells, and they are not unfrequently sub-divided by walls of secondary origin (Fig. 63). According to .Smith, the cells of the palisade parenchyma have also thickened walls, as well as behig elongated and occasionally chambered ; the cells of the spongy parenchyma are enlarged and have thicker walls; so also are the cells of the collenchyma of the leaf Leaf of Po'iiut-us Fui. C'i.—h'joannis o; niyru, showinp the ptistulc-like swellings.' Tnbeiif del.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readabilit
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherl, booksubjectfungi
