. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. 168 ASCOMYCETES. the upper surface of the leaf (Fig. 64), and the upper epidermis alone bears the asci. In the pustules, the leaf may be two to four times as thick as healthy parts. The greatly increased thickness is due for tlie most part to enlargement of the cells of tlie mesophyll, while at the same time their normal arrangement is completely lost (Figs. Q5, 66). The elements of the libro- vascular bundles are enl
. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. 168 ASCOMYCETES. the upper surface of the leaf (Fig. 64), and the upper epidermis alone bears the asci. In the pustules, the leaf may be two to four times as thick as healthy parts. The greatly increased thickness is due for tlie most part to enlargement of the cells of tlie mesophyll, while at the same time their normal arrangement is completely lost (Figs. Q5, 66). The elements of the libro- vascular bundles are enlarged; the cells of the upper epidermis are more nmnerous, contain a reddish sap, and their walls are thickened. All cldorophyll is destroyed in the pustules. Ex. polysporus (Sor.) causes swollen spots on leuA^es of Ace7' tartaricum. Ex. buUatus (Fuck.) causes similar '^ spots on leaves of pear {Fyrus ^^ communis) and quince {Cydonia \_ jcifponica). [, Ex. Sadebeckii (Johan.) causes simple spots on leaves of Alnns i/hifiiw-'^a. Many other species, named in our list and in Sad check's papers, will be found described in detail in one or other of the papers already cited. K Fici. Ii~.—Exoaicm poli/sporus on Ac(r tartaricum from Sweden. The attacked leaf Hhows pule spots with brown centres. The former result frmii the To/>ltriita, and .ire covered liy a white coating; of asci; the brown Mjiots are produced by other fungi which grow on the spots already killed. I nat. .size. (v. Tubeuf del.) Jl Carpoasci. {Ascomycetes loith SporocurjL/s.) The asci of the Carpoasci. are not formed directly on the mycelium, but from a special part of it, which becomes more or less enclosed in another non-ascogenous portion. From these two portions of the mycelium a sporocarp is formed, in which we can distinguish three distinct constituents: (a) the envelope containing (b) the paraphyses and (c) the asci. Amongst the Gyranoasci the envelope, if present, is never more than a loose hyphal ti
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherl, booksubjectfungi
