. Transactions. Fig. 1. Nuung LuilIi su ^iKiuMi^ A^cocarps of JVziza size. When the ascocarps reach a certain stage of growth they producelarge numbers of minute spores, which are canied by the wind toother trees. There they germinate and push what may popularlybe called a rootlet (germ tube) into those living tissues of the 367. tree which are commonly called the bark. This primary rootletsoon breaks up into a number of other rootlets (mycelia), so thatin a short time a regular network is formed, which attack and killall living cells with which they come into contact. (See
. Transactions. Fig. 1. Nuung LuilIi su ^iKiuMi^ A^cocarps of JVziza size. When the ascocarps reach a certain stage of growth they producelarge numbers of minute spores, which are canied by the wind toother trees. There they germinate and push what may popularlybe called a rootlet (germ tube) into those living tissues of the 367. tree which are commonly called the bark. This primary rootletsoon breaks up into a number of other rootlets (mycelia), so thatin a short time a regular network is formed, which attack and killall living cells with which they come into contact. (See Fig 2.) In this way all thecells of the cortex,bast, and cambiumat the point of attackare destroyed; and,as the cambium is thetissue which producesthe wood, it followsthat no wood is formedon the part of the stemwhich is occupied bythe parasite. Eachyear the fungus makessome progress andembraces more and ^ „ ^ „ ~ r X , 1 • , more of the cam- FiG 2. Bast cells of a Larch, snowing themycelia of P. Willkommii, magnified 400 times, bium ; and if the(From Mr. Carruthers paper in the Journal of growth of the parasitethe ) proceeds at a greater rate than the growth of the tree, the cambium will be killed right round the stem at the place attacked, and the tree will ultimately succumb. The history of the progress of the disease may b
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Keywords: ., bookcentury1800, bookdecade188, bookpublisherlondon, bookyear1883
