Page:The Journal of Indian Botany.djvu/691

PLANTS OF THE INDIAN DESERT. 225 ones found in the medullary tissue and enclosed in stereome rings. Mechanical tissue in the axis in the form of stereome tube. Medull- ary tissue of thick- walled cells.

Andropogon foveolatus Del— Figs. 331, 332, 333. Not much grooved on either surface. Margin blunt and with large stereome bundles. Hairs unicellular, long and bluntly pointed. Articulation tissue one-layered groups. Palisade tissue and bundle-sheaths in the form of rings round smaller veins and of arcs on sides of vertically transcurrent veins. Mechanical tissue in the leaf sin the form of I-girders in association with vertically transcurrent veins and of isolated sub-epidermal girders on the lower side of other veins. T. S. of the axis horseshoe shaped. Mechanical tissue in the axis forming a sub-epidermal stereome tube. Assimilatory tissue absent in the axis. Smaller bundles embedded in stereome tube. Larger bundles few in the medullary tissue. Medullary tissue of thin-walled cells.

Andropogon annulatUS Forsk — Fig. 334. Not much grooved on either side. Margin pointed and with large stereome bundles. Hairs unicellular, long and bluntly pointed. Articulation tissue in the form of one layered groups. Palisade cells and sheath-cells forming complete rings round smaller veins and arcs on sides of vertically transcurrent veins. Mechanical tissue in the leaf in the form of I-girders in association with vertically transcurrent veins and of isolated sub-epidermal girders on the lower side of other veins. T. S. of the axis horse-shoe shaped. Mechanical tissue in the axis forming a sub- epidermal stereome tube. Assimilatory tissue absent in the axis. Smaller bundles embedded in the stereome tube. Larger bundles few in the medullary tissue. Medullary tissue of thin-walled cells.

Aristida funiculata Rupr — Figs. 335, 336, 337, 338. Upper surface deeply grooved. Margins bluntly pointed and with large stereome bundles. Hairs spiny. Palisade tissue and sheath-cells forming complete girders round smaller veins and arcs on sides of vertically transcurrent veins. Mechanical tissue in the leaf in the form of I-girders in association with vertically transcurrent veins and of isolated sub-epidermal girders on the lower side. Mechanical tissue in the axis forming a stereome tube supplimented by sub-epidermal I-girders. Webs formed by unmixed vascular bundles or by strips of stereome. Assimilatory tissue in the axis chlorenchymatous. Larger bundles in the medullary tissue and few. Medullary tissue of thin- walled cells.

Aristida hirtigluma Steud.— Figs. 339, 340. Grooves on the upper surface not deep. Margin pointed and with small stereome bundles. Hairs spiny. Articulation tissue only in the upper half of mesophyll. Palisade tissue and sheath cells forming complete rings