. Fio. 13.—Tracheid of Finns sylcestris destroyed by Tmmetes jiini. The primary cell-Wall is completely dissolved from below upwards to n, a ; b, secondary and tertiary layers of the walls consisting in the under portion of cellulose only, in wliich granules of chalk are recognizable ; c, fungus-hyphae boring through the walls, leaving holes d and e. (After R. Hartig.) Fi(i. 14.—Tracheid of Pinu-t destroyed by Poh/poms Schweinitzii. The cellulose has been extracted, and the wall consists only of wood-gum. The fissures are a result of drying-up, but they do not extend into the primary wall a, h
. Fio. 13.—Tracheid of Finns sylcestris destroyed by Tmmetes jiini. The primary cell-Wall is completely dissolved from below upwards to n, a ; b, secondary and tertiary layers of the walls consisting in the under portion of cellulose only, in wliich granules of chalk are recognizable ; c, fungus-hyphae boring through the walls, leaving holes d and e. (After R. Hartig.) Fi(i. 14.—Tracheid of Pinu-t destroyed by Poh/poms Schweinitzii. The cellulose has been extracted, and the wall consists only of wood-gum. The fissures are a result of drying-up, but they do not extend into the primary wall a, h. Crossing of the fissures takes place at the bordered pits c, and at the bore-holes d and e; /, simple fissures. (After R. Hartig.) kind, the primary wall, containing but little cellulose, is hardly affected, and the secondary meml;)ranes shrink together, so that numerous fissures are produced running in a spiral direction, corresponding with that of the stratification (Figs. 13 and 14.) The tertiary membrane varies in its nature ; it may consist of pure cellulose or be more or less lignified, or even cuticularized. In the wood-fibres of some plants {Cytisus, Htimulus,) this
Size: 1231px × 4062px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublisherl, booksubjectfungi
