Page:The Journal of Indian Botany.djvu/525

 THE Journal of Indian Botan-p. Vol. II. JUNE, 1921. Nos. 4 & 5.

THE PHYSIOLOGICAL ANATOMY OF THE PLANTS OF THE INDIAN DESERT BY T. S. Sabnis, B.A., M.SC, St. Xavier's College, Bombay. (Continued from p. 73.)

SCROPHULARIACEAE.

Anticharis linearis Hochst— Fig. 245 (Axis only). Epi- dermal cells tabular. Cuticle smooth. Guard-cells elevated. Trie- homes straight and smooth-walled. Cells of the outermost layer of cortex showing collenchymatous differentiation. Pericycle forming a loose ring of groups of bast fibres. Wood-ring broad. Vessels small and arranged in incomplete long rows. Interfascicular wood pro- senchyma extensive and formed of cells with thick walls and with small lumen. Medullary rays uniseriate and numerous. Pith of thin-walled cells.

Schweinfurthia sphaerocarpa Braun.— Figs. 246, 247. Epi- dermal cells of the leaf and axis tabular. Large conical unicellular knobbed hair-like structures intercalated amongst ordinary epidermal cells. Cuticle striated. Trichomes curved and with walls covered with cuticular knobs. Mesophyll bifacial. Guard-cells elevated. Stomata on both the surfaces. Cells of the outermost layer of cortex showing collenchymatous differentiation. Pericycle in the form of isolated bast fibres. Wood-ring narrow. Vessels large and arranged in complete rows. Medullary rays absent. Interfascicular wood prosenchyma little developed and composed of cells with thin walls and large lumen. Pith of thin-walled cells.

Structure of the Leaf.— The epidermis in S. sphaerocarpa (fig. 246) consists on both sides of tabular cells with the outer walls greatly CM