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 



523—30 



