Plants and their ways in South Africa . r for the over the under surfaceof the Apricot leaf are very smallholes called stomates (singularstoma) or stomata (mouths). Twocrescent-shaped cells surround theopening. These lip cells open andclose. During the day they areopen, and evaporation keeps theleaves cool. If leaves were as hotas the stones around them theywould die. In very dry weatherthe stomata close so that less waterescapes. These stomata open intospaces within the leaf into whichwater passes from surrounding a summer day leaves lift upand lose tons of water. L
Plants and their ways in South Africa . r for the over the under surfaceof the Apricot leaf are very smallholes called stomates (singularstoma) or stomata (mouths). Twocrescent-shaped cells surround theopening. These lip cells open andclose. During the day they areopen, and evaporation keeps theleaves cool. If leaves were as hotas the stones around them theywould die. In very dry weatherthe stomata close so that less waterescapes. These stomata open intospaces within the leaf into whichwater passes from surrounding a summer day leaves lift upand lose tons of water. Leavesborne on the surface of water or close to the soil have theirstomata on the upper surface.^ The Water Path from Root to Leaves.—Water doesnot pass up to the leaves through all parts of the stem. If aBegonia stem is placed in water coloured with red ink, in a fewhours the ink will mark the path it has taken. Cut the stem ^ An area on the under surface which could be covered by the capitalO on this page contains over 3000 Fig. 68.—I. Horizontal sectionthrough the epidermis ot theunder side of the leaf of Eu-onytnus japo7iiats looked atfrom below ; sp, stomata. of development of thestoma of Arthropodium cir-fhatuni: spm, mother - cellready for division ; sp, sp,sp, successive stages of divi-sion. III. Mature stoma.(From Edmonds and Mar-loths Elementary Botanyfor South Africa.) 62 Plants and their Ways in South Africa across and the paths will show as small round dots. They showplainly in Pumpkin stems as strong slender threads. Thesethreads are bundles of still smaller tubes or vessels, and so thestrands are known as vascular bundles. Break off a Violetleaf; the vascular bundle may be drawn out from the brokenend. The petioles of Plantain or Wild Sago, which grows along P
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1915
