. A practical course in botany, with especial reference to its bearings on agriculture, economics, and sanitation. Botany. coloring fluid a short time before the lesson begins. The leafstalks of celery and plantain are excellent for showing the relation between the leaf veins and vascular system of the plant. 171. Parallel and net veining. — Compare a leaf of the wandering Jew, lily, or any kind of grass, with one of grape, ivy, or willow. Hold each up to the light, and note the veins or little threads of woody substance that run through it. Make a draw- ing of each so as to show plainly the d
. A practical course in botany, with especial reference to its bearings on agriculture, economics, and sanitation. Botany. coloring fluid a short time before the lesson begins. The leafstalks of celery and plantain are excellent for showing the relation between the leaf veins and vascular system of the plant. 171. Parallel and net veining. — Compare a leaf of the wandering Jew, lily, or any kind of grass, with one of grape, ivy, or willow. Hold each up to the light, and note the veins or little threads of woody substance that run through it. Make a draw- ing of each so as to show plainly the direc- tion and manner of veining. Write under the first, parallel-veined, and under the second, net-veined. This distinction of leaves into parallel and net-veined cor- responds with the two great classes into which seed-bear- ing plants are divided, mon- ocotyls, as a general thing, being characterized by the first kind, and dicotyls by the second. 172. Pinnate and palmate veining. — i 206. —Net- Next, compare a leaf of the canna, calla lily veined leaf of a wil- or any kincl 0f arunl) with One of the elm peach, cherry, etc. What resemblances you notice between the two? What differ- ences ? Which is parallel-veined and which is net-veined ? Make a drawing of each, and compare with the first two. Notice that in leaves of this kind, the petiole is continued in a large central vein, called the midrib, from which the secondary veins branch off on either side like the pinnae of a feather; whence such leaves are said to be pinnately, or feather veined, as in Figs. 206, 207. In fig. 207.—Pin- the cotton, maple, ivy, etc., on the other lately paraUei- hand, the petiole breaks up at the base of the my (After Gbat). Fig. 205.—Par- allel-veined leaf of lily of the valley (After Gray). do. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly
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Keywords: ., bookauthorand, bookcentury1900, bookdecade1910, booksubjectbotany
