# The Journal of Indian Botany/Volume 1/May 1920/The Physiological Anatomy of the Plants of The Indian Desert

Layout 4
​THE
Journal of Indian Botany*
Vol. I. MAY, 1920. Nos. 9 & 10.
THE PHYSIOLOGICAL ANATOMY OF THE PLANTS OF THE INDIAN DESERT
BY
T. S. Sabnis, B.A., M.Sc
St. Xavier's College, Bombay. t (Continued from p. 2i7.)
LYTHRACEAE—(Contd.)
The mesophyll is composed of palisade tissue on the upper side and of arm-palisade tissue on the lower. Internal secretory organs are not found. Oxalate of lime occurs in the form of clustered crystals near the veins in A. desertorum.
The veins are embedded and are enclosed in green bundle- sheaths.
Hairy covering is found on the axis and on bhe upper surface of the leaf of A. desertorum and consists of unicellular conical hairs with verrucose walls and sometimes seated on a group of two or three epidermal cells (fig. 126). Glandular hairs are not found.
Structure of the Axis : — The epidermis is composed of tabular cells with outer walls thickened, verrucose and convexly arched out- wards. The inner walls are thickened; and the lateral walls are thin and straight. The axis is ribbed at the angles. The cortex is composed of chlorenubyma extending to the ribs.
The pericycle forms a loose ring of bast fibres, those in A. bacci/era having thin walls and large lumina. The wood is composite. The vessels are uniformly distributed in incomplete rows, vessels becoming larger towards the inner margin of the wood. The interfascicular wood prosenchyma is composed of cells with thin walls and large lumina and is more extensive in the upper half. The medullary rays are uniseriate and numerous. Wood parenchyma is abundantly developed at the inner margin of the wood cylinder. ​ The pith is composed of thin-walled cells and is characterised in A. baccifera by small groups of thick-walled cells, having the same size and shape as that of the pith cells. These cells form probably the strengthening tissue of the pith.
ONAGRACEAE
Trapa bispinosa Roxb.— Fig. 127. Leaf only.— Epidermis formed of tabular cells with outer walls very greatly thickened on the upper surface. Stomata occurring only on the upper surface. Clothing hairs in the form of uniseriate trichomes and found only on the lower surface. Mesophyll formed of palisade tissue on the adaxial side and of spongy tissue on the abaxial side. Spongy tissue characterised by large intercellular spaces. Oxalate of lime found in the form of numerous clustered crystals. Veins embedded and not provided with bundle-sheaths.
Structure of the Leaf. — The epidermal cells are tabular and thin-walled on the lower surface. The outer walls of the epidermal cells on the upper surface are very greatly thickened. The lateral walls are straight. Stomata occur in large number only on the upper surface and are surrounded by ordinary epidermal cells. Guard- cells are situated in the plane of the surrounding cells and the front cavity is on a level with the surface. Closure of the stomata seems to take place by the well developed cuticular ridges of the guard-cells (fig. 127).
Hairy covering consists of long uniseriate thin-walled trichomes occurring only on the lower surface (fig. 127). External glands are not found.
The mesophyll is composed of long-celled palisade tissue on the adaxial side and of spongy on the abaxial side which is characterised by large intercellular spaces. The system of large intercellular spaces helps the leaves to float on the surface of water.
Internal secratory organs are not found. Oxalate of lime occurs in the form of numerous clustered crystals in the spongy tissue. The cells containing clustered crystals are arranged in small groups projecting into the intercellular spaces. Larger clustered crystals are isolated and occur in the palisade tissue.
The veins are embedded and are not enclosed in bundle-sheaths.
CUCURBITACEAE
Momordica dioica Roxb.— Figs. 128, 129, 130. 131. Leaves membraneous. Guard-cells elevated. Mesophyll formed of short- celled palisade tissue on the upper side and of spongy tissue on the lower. Trichomes on the leaf provided with subsidiary cells not ​elevated above the base of the trichomes. Cystolith-like structures not found in the basal cells of the trichomes. Branches deeply fur- rowed. Pericycle forming a continuous undulated ring of stone-cells. Oollenchyma developed in the angles.
Cucumis Melo L.— Figs. 132, 133, 134. Guard-cells elevated above the epidermis. Mesophyll composed of short-celled palisade tissue on the adaxial side and of spongy tissue on the abaxial side, Trichomes on the leaves provided with subsidiary cells not raised above the base of the trichomes. Axis obtusely angular with stiff long trichomes on the ridges. Oollenchyma forming a continuous un- dulated ring below epidermis. Cystolith-like structures in the basal cells of the trichomes on the leaf. Some of the cells of soft bast as well as some of those of the ground tissue, separating the vascular bundleSi with tanniniferous contents. Pericycle forming a continuous ring of stone-cells.
Citrullus Colocynthis Schrad.— Figs. 135, 136. Guard-cells much elevated above the epidermis. Mesophyll formed of long-celled palisade tissue on the adaxial side and of arm-palisade tissue on the* abaxial side. Trichomes on the* leaf provided with subsidiary cells raised above the base of the trichomes. Cystolith-like structures found in the basal cells of the trichomes on the leaf. Groups of colourless palisade-like cells below the lower epidermis forming water- cells. A few cells of soft bast with tanniniferous contents. Axis not much angled. Pericyule formed of closely placed groups of stone-cells. Oollenchyma developed in the larger angles.
Melothria maderaspatana Cogn.— Figs. 137, 138. Guard- cells much elevated above epidermis in the loaf ; and situated on a pedestal on the axis. Mesophyll formed of long-celled palisade tissue on the adaxial side and of spongy tissue on the abaxial side. Trichomes on the leaf provided with subsidiary cells not much raised above the base of the trichomes. Cystolith-like structures found in the basal cells of the trichomes. A few cells of soft bast with tanniniferous contents. Pericycle forming a continuous undulat- ed ring of stone-cells. Axis deeply furrowed. Oollenchyma developed in the ridges. Structure of the Leaf. — The epidermis consists of polygonal cells with outer walls a little thickened. The lateral walls are undulated. Cystolith-like structures occur in the basal epidermal cells of the trichomes on the leaf except in Momordica dioica. The stomata are more numerous on the lower surface and are surrounded by ordinary epidermal cells. The guard-cells are elevated. The front cavity i placed in a depression formed by th9 outer thickened epidermal walls in species of Citrullus ; in species of other genera it is situated on a ​level with the surface. The sfcomaba on the axis are found at the apex of pedestals formed by epidermal cells. The pedestals are quite conspicuous in Melothria viaderaspatana (tig. 138).
The mesophyll is composed of palisade cells, which are much shorter in Momordica dioica and Cucumis Melo, on the adaxial side and of an extensive spongy tissue on the abaxial side. The spongy tissue is replaced by arm-palisade tissue in Citrullus Colocynthis. There are groups of colourless palisade-like cells below the lower epidermis of Citrullus Colocynthis ; these groups of cells may form water-cells.
The veins are embedded and are not provided with bundle-sheaths. They are vertically transcurrent.
The hairy covering consists of clothing and glandular hairs. The clothing hairs are more numerous on the lower surface and consists of simple uniseriate thin-walled trichomes seated on subsidiary cells which are raised above the base of the trichomes in Cucumis Melo (fig. 134) and in Melothria maderaspatana. The trichomes on the axis are accompanied by numerous subsidiary cells, which form a pelestal-like structure (fig. 132). The constituent cells of the trichomes are dilated at the base, thus giving them a somewhat jointed appearance.
The external glands on the leaf and axis are composed of a short uniseriate stalk usually placed in epidermal depressions and of an ovoid head divided by horizontal and vertical walls. Glandular hairs seem to be more numerous on the upper surface in Momordica dioica.
Structure of the Axis. — The epidermis consists of small polygonal cells with outer walls a little thickened. Axes are deeply five-grooved except in Citrullus Colocynthis where the ridges and the furrows are very slight.
The cortex is characterised by an assimilatory tissue formed of chlorenchyma. The collenchyma is sub-epidermal ; it is developed in the angles in Momordica dioica and in Melothria maderaspatana (fig. 136) ; in Cucumis Melo it forms a continuous ring thickened in the angular portions. In Citrullus Colocynthis collenchyma is developed below the epidermis of the larger angles.
The pericycle forms a composite undulated ring of stone-cells except in Citrullus Colocynthis where it is composed of closely placed groups of stone-cells.
The vascular bundles are bicollateral and are arranged in two rings five in each ring. The bundles in the outer ring are much smaller and occur below the angles where they are conspicuous. Smaller bundles project towards, the exterior and the larger towards ​the interior. The bundles are oonnected together by broad strips of ground tissue which resemble medullary rays. Bundles in the inner ring almost meet in the centre in Gitridlus Golocynthis and in Melothria maderaspatana. The vessels expecially those of the bundles of the inner ring have very wide lumina.
A few cells of soft bast on either side of the bundles hold tanni- niferous contents in all members etcept Momordica dioica.
The pith is greatly reduced on account of the bundles of the inner ring projecting inwards. It consists of a few thin-walled cells.
General Review. — The epidermal cells have outer walls a little thickened. The mesophyll is bifacial. Stomata are usually elevated above the epidermis, much more so on the axis where they are usually situated at the apex of pedestals formed by the subsidiary cells. The stomata, as a rule, are more numerous on the lower surface of the leaf. The hairy covering consists of uniseriate thin-walie I triohomes seated on subsidiary ceils which, on the axis, are raised above the base of the trichomes in the form of a pe lestal. The trichomas are some- what jointed and more numerous on the lower surface of the leaf. Internal secretory organs ate represented by a few isolated cells of soft bast with tanniniferous contents in all members except Alomor- dica dioica. The glandular hairs are placed in epidermal depressions and consist of a short uniseriabe stalk and of an oval head divider by horizontal and vertical walls. The pericycle forms a continuous and undulated ring of stone-cells or it is formed of closely placed groups of stone-sells. Gollenchyma is developed below the epidermis of the angles. The vascular bundles are bicollateral and are situated roughly in two rings. The bundles of the outer ring are much smaller and are situated below the angles; bundles belonging to the inner ring are much larger and are placed below the furrows; smaller and larger bundles project outwards and inwards respectively. The bundles are separated from one another by broad strips 01 ground tissue resembling medullary rays. The vessels have wide lumina and simple perforations. The pith is greatly reduced as the bundles of the inner ring almost meet in the centre.
FICOIDEAE
Trianthema triquetra Bottl. & Wild.— Figs. 139, 140. Leaves fleshy. Mesophyll characterised by an extensive aqueous tissue. Stomata found only on the lower side of the leaf. Arcs of palisade cells on the lower side. Veins embedded and half enclosed with green bundle-sheaths. Clustered crystals found near the veins, in the cortex and in the pith. Some of the epidermal cells bladder-like and atte- nuated at the apices into hair-like structures, Axes angled, Wood ​belonging to the second type. Groups of soft bast embedded in the wood cylinder. Pith formed of thin-walled cells.
Trianthema pentandra L.— Figs. 141, 142, 143. Some of the epidermal cells bladder-like and attenuated at their apices into hair-like structures. Mesophyll bifacial. Clustered crystals near the veins, in the cortex and pith. Veins provided with green bundle-sheaths. Branches angled and grooved. Sclerenchymatous pericycle not developed. Wood belonging to the second type. Pith formed of thick-walled cells.
Orygia decumbens Forsk.— Figs. 144, 145, 146, 147. Me- sophyll composed of palisade tissue on the adaxial side and of arm- palisade tissue on the abaxial side. Veins not provided with bundle- sheaths. Clustered crystals found near the veins, in cortex and in pith. Axes obscurely angled. Assimilatory tissue in the axis formed of chlorenohyma. Collenchyma developed in the angles. Pericycle forming a composite ring of stone-cells. Wood belonging to the third type. Pith formed of thin-walled cells.
MollugO hirta Thunb. — Figs. 148, 149, 150. Clothing hairs forming a dense covering of stellate hairs. Mesophyll isobilateral. Star-like bundles of acicular crystals in the mesophyll. Veins embedded and without bundle-sheaths. Assimilatory tissue formed of chlorenchyma. Clustered crystals found in the cortex and in the pith. Pericycle formed of a composite ring of atone-cells. Pith composed of thin-walled cells.
Mullugo nudicaulis Lam.— Figs. 151, 152, 153. Mesophyll bifacial. Styloids found in the spongy tissue. Veins embedded and without sheaths. Clustered crystals in the neighbourhood of the veins. Assimilatory tissue in the axis formed of chlorenchyma. Structure of wood belonging to the first type. Pith formed of thin- walled cells.
Mullugo Cerviana Ser. — Figs. 154, 155. Some of the epider- mal cells larger and with water-storing function. Mesophyll isobila- teral. Veins embedded and provided with green bundle-sheaths. Assimilatory tissue in the axis in the form of chlorenchyma. Scleren- chymatous pericycle forming a composite ring. Structure of wood belonging to the first type. Pith formed of thin-walled cells.
Gisekia pharnaceoides L. — Fig. 156. Leaves sub-fleshy. Mesophyll bifacial. Veins embedded and without bundle-sheaths. Bundles of acicular crystals found near the veins, in the cortex and in the pith. Axes angled. Sclerenchymatous pericyole forming a composite ring. Structure of wood belonging to the third type. Pith formed of thin-walled cells.
Limeum indicum Stocks.— Figs. 157, 158, 159. Some of ​the epidermal cells large and having water-storing function. Mesophyll isotailateral. Clustered crystals found near the veins and in cortex. Hair-like structures, with walls thickened and superficially rugose, found on the leaf. Perioycle formed of rhomboidal groups of stone- cells, Pith formed of thick-walled cells.
Structure of the Leaf. — The epidermis consists of polygonal cells with outer walls thickened, papillose and superficially granulated, except in species of Mollugo in which the cells are very thin-walled. The thickening of the outer walls is considerable in L. indicum (fig. 157). Some of the epidermal cells in T. pentandra (fig. 114) are bladder-like and are attenuated at their apices into hair-like structures ; they are numerous on the lower side of the mid-rib. There are also, in M, Gerviana and L. indicum, large cells intercalated amongst the epidermal cells of ordinary dimensions. All these specialised cells seem to have the function of absorbing and storing water. The lateral walls are thin and undulated.
The thinness of the outer walls, specially in M. hirta and M Gerviana, can be accounted for by the presence of a protective covering of dense stellate hairs and by the occurrence of large water-storing epidermal cells.
The stomata are usually numerous on both the surfaces of the leaf and are surrounded by ordinary epidermal cells. The front oavity is placed in a depression formed by outer thickened and papil- lose epidermal walls (figs. 145, 158). The stomata in T, triquetra (fig. 139) are elevated and occur only on the lower surface, owing to the occurrence of an extensive aqueous tissue on the upper surface. The guard-cells are usually elevated, though in T. triquetra, T. pent- andra and in M. Gerviana elevated guard-cells occur side by side with guard-cells situated in the plane of the surrounding cells. The stomata are, as a rule, numerous and can be accounted for by the fleshy character of the leaf.
The mesophyll is isobilateral'in M. hirta (fig. 150) and M. Cerviana (fig. 154), in other members it is bifacial. The mesophyll, in T. Pen- tandra (fig. 141), M. nudicaulis (fig. 151) and G. pharnaceoides, con- sists of palisade tissue on the upper side and of spongy tissue on the lower. The structure of the mesophyll in T. triquetra is characteristic ; it consists on the abaxial side of a subepidermal aqueous layer and of arcs of palisade cells on the lower side of the veins and on the adaxial side of an extensive aqueous tissue of large polygonal cells. In 0. dccumbens and L. indicum (fig. 157) there is palisade tissue on the upper side and arm-palisade tissue on the lower.
Internal secretory organs are not found in the leaf and axis. Oxalate of lime occurs in the form of numerous large clustered cry​stals in the neighbourhood of the veins in T. triquetra, T. pentandra, 0. decumbens, M. nudicaulis and L. indicum. Besides clustered crystals near the veins, there are solitary ones in the spongy cells of M. nudi- caidis (fig. 151). Palisade cells on both sides, in M. hirta (fig. 150) and M. Gerviana (fig. 154), contain small bundles of needle-like crystals and solitary crystals respectively. Oxalate of lime is found in the form of bundles of acicular raphides in G. pharnaceoides.
The veins are embedded in all members ; they are provided with bundle-sheaths of green, thin-walled cells in T. pentandra and M. Cerviana. Sheath-cells are colourless in L. indicum. Veins in T. triquetra, are provided only on the lower side with arcs of green bundle-sheath cells, owing to the occurrence of the assimilatory tissue on the sides of the veins.
Hairy covering on the leaf and axis is found only in M. hirta and consists of stellate hairs with an uniseriate stalk and a star-shaped terminal cell (figs. 148, 149, 150). In L. indicum (fig. 157), there are papillae-like unicellular structures with walls thickened and superfi- cially rugose. They may have been developed from epidermal out- growths which were afterwards separated by transverse walls ; they may have a water-storing function. External glands are found only in L. indicum in the form of capitate glandular hairs (figs. 157, 159).
Structure of the Axis. — The epidermis consists of polygonal cells with outer walls thickened. Lateral walls are thin and undulated Inner walls are also thickened in T. triquetra, T. pentandra, 0. decumbens, M. hirta and G. phamaceoide. There are large bladder- like cells, attenuated at their apices into hair-like structures, inter- calated among-it epidermal cells of ordinary dimensions in T. triquetra (fig. 140) and in T. pentandra (fig. 143). These cells may have a water-storing function. The stomata are like those on the leaf.
The primary cortex is represented by a thin-walled parenchy- matous assimilatory tissue in 0. decumbens and in species of Mollugo. Collenchyma is developed in the angular portions of 0. decumbens. The primary cortex, in other members, is formed of colourless cortical parenchyma.
The pericycle is formed of a more or less composite ring of stone- cells in 0. decumbens (fig. 146), species of Moll tig o (figs. 149, 153, 155) and G. pharnaceoides. In species of Moll tig o the ring of stone tissue is very thick. The pericycle in L. indicum, consists of rhomboidal groups of stone-cells ; in other members it is not sclerenchymatous, which is compensated for perhaps by extensive interfascicular wood prosenchyma which is very little developed in species of Mollugo. It seems, therefore, that the development of sclerenchymatous pericycle is inversely proportional to that of interfascicular wood prosenchyma. ​ The wood is composite in all members. In species of Trian- thema it is composed of numerous xylem bundles which are embedded in interfascicular wood prosenchyma in more or less distinct concentric rings (figs. 140, 143). In species of Mollugo it is composed of large xylem bundles with vessels large and numerous and with little interfascicular wood prosenchyma (figs. 149, 153, 155). Vessels, in 0. decumbens, G. phamaceoides and L. indicum, are large and numerous and are uniformly distributed in the interfascicular wood prosenchyma. Thus the structure of the wood can be classified into three types — M, nudicaulis and M. Cerviana representing one type species of Trianthema another and 0. decumbens, M. hirta, G. phama- ceoides and L. indicum the third type.
The structure of the wood has undergone modifications
    (1) either due to the decumbent habit as in 0. decumbens in
which the wood cylinder is very much narrowed and the vessels are few and small on the lower side of the axis.
    (2) or to the direction of the prevailing wind as in T. triquetra,
G. phamaceoides and L. indicum, in which larger xylem bundles with vessels larger and more numerous occur on two opposite sides of the axis which represent the plane of the direction of the prevailing wind, while in a plane at right angles to this occur much smaller xylem bundle with vessels much smaller and less numerous.
These modifications are the result of greater functional activity on those sides which are more affected by wind in the case of erect axes, or by the sun and wind together in case of prostrate axes.
The pith consists of thick-walled calls in T. pentandra, M. hirta and L. indicum; in other members it is formed of thin-walled cells.
Oxalate of lime is found in the form of clustered crystals in the cortex and pith of T. triquetra, T. pentandra, 0. decumbens and M, hirta ; in L. indicum clustered crystals occur only in the cortex. Acicular crystals are found in the cortex and pith of G. phamaceoides.
Anomolous structures are represented by groups of soft bast embedded in the wood cylinder in T. triquetra.
General Review. — 'Epidermis consists of polygonal cells with outer walls usually thickened. Large bladder-like cells with water- storing function are intercalated amongst epidermal cells (figs. 141, 143). Stomata are depressed and are accompanied by ordinary epidermal cells. The mesophyll in T. triquetra (fig. 139) is character- ised by an extensive aqueous tissue. Oxalate of lime is found in the form of clustered crystals in the leaf and axis of most of the members. Styloids occur in M. nudicaulis and M. Cerviana; acicular crystals are present in G. phamaceoides. Hairy covering is present only an M. hirta ​and consists of stellate hairs. There are unicellular papillae-like— structures in L. indicum, (fig. 157), with walls superficially rugose and perhaps with a water-storing function.
The pericycle is composed of stone-cells, except in species of Trianthema. Wood is composite and can be classified into three types as described already. The structure of the wood undergoes modifi- cations either due to the prostrate habit of the axis or to the action of wind in case of erect axes. The perforations of the vessels are simple. The pith consists of thin-walled or thick-walled cells.
RUBIACEAE
Oldenlandia aspera DC— Fig. 162. Epidermal cells with outer walls convexly arched outwards. Mesophyll formed of short-celled palisade tissue. Unicellular dome-like structures with thickened and muriculate walls found on the axis. Epidermal cells of the axis with both outer and inner walls thickened. Internal secretory organs and oxalate of lime not found. Sclerenchymatous pericycle absent. Soft bast of thick walled-cells. T. S. of the axis circular.
Spermacoce hispida L. — Figs. 160, 161. Upper epidermal cells larger and with outer walls usually toothed in the middle. Mesophyll composed of palisade tissue on the upper side and of spongy tissue on the lower. Internal secretory cells with tanniniferous con- tents numerous in the mesophyll. Secretory cavities found in the mesophyll and cortex. Acicular crystals found in the cortex. Cloth- ing hairs in the form of articulated uniseriate trichomes. Epidermal cells of the axis with outer walls thickened. Axes quadrangular. Angles bearing wing-like ribs. Pericycle forming a loose ring of bast fibres.
Structure of the Leaf. — The epidermal cells are polygonal with the outer walls greatly thickened and convexly arched outwards. The outer walls of the upper epidermal cells of S. hispida are toothed in the middle, while those of the epidermal cells on both the surfaces in 0. aspera are sometimes papillose. Lateral walls are thin and undulated ; inner walls are thin.
The stomata are accompanied by subsidiary cells and are more numerous on the lower surface. The guard-cells are situated in the plane of the subsidiary cells which are elevated above the surrounding cells. The front cavity is placed in depressions formed by the outer thickened walls of the surrounding cells. The stomata on the axis have the same characters as of those on the leaf (Gg. 162).
The mesophyll in 0. aspera is composed wholly of short palisade cells ; it is bifacial in S. hispida. Internal glands occur -only in S, hispida, and are represented by mucilaginous secretory ^cavities ​with acicular raphides (fig. 160) in the assimilatory tissue in the leaf and axis. Besides these, there are assimilatory cells in the mesophyll with tanniniferous contents (fig. 160 G.).
Oxalate of lime occurs only in S. hispida either in the form of acicular raphides in the mesophyll and pith (fig. 161 A. E.), or in the form of crystal sand in the cortex. The vains are embedded and are not provided with bundle-sheaths. "Veins of the mid-rib are vertically transcurrent above and below by collenchyma in 0. aspera.
The hairy covering on the leaf and axis in S. hispida (figs. 160, 161) consists of articulate uniseriate trichomes with the terminal cell ending in a sharp point ; trichomes on the axis are situated in groups on the wiug-like ribs at the angles (fig. 161). Trichomes are more numerous on the lower surface of the leaf. Clothing hairs are absent on the leaf of 0. aspera ; on the axis, however, there are peculiar dome-like unicellular hair-like structures with walls thickened and muriculate. Glandular hairs are not found on the leaf and axis.
Structure of the Axis. — The epidermis consists of tabular cells with outer walls greatly thickened. The outer walls are muriculate and the inner walls also thickened in 0. aspera (fig. 162). The lateral walls are thin and straight. There are large wing-like ribs at the angles of the axis in S. hispida. The cortex of S. hispida is composed of parenchymatous assimilatory tissue extending into ribs which are strengthened by collenchyma. Assimilatory cells contain rounded bodies of the nature of fat bodies. Endodermis is differentiated. Sclerenchymatous pericycle is found only in S. hispida and is com- posed of a loose ring of bast fibres.
The vessels are arranged in complete rows and are larger in the lower half of the wood. Interfascicular wood prosenchyma is scantily developed and is formed of cells with thin walls and with large lumina. Medullary rays are uniseriate and numerous. The abundance of vessels and the scanty development of interfasicular wood prosencby ma are characteristic of the herbaceous nature of the plants.
The pith is composed of thin-walled cells.
(To be continued.)
Plate XV
128-131. Idomordica dioica.
128. Hair on the leaf.
Oc. 4 Com. ; Ob. 3 mm. Ap.
129. T. S. of the leaf showing the upper epidermis.
Oc. 4 Com. ; Ob. 3 mm. Ap.
130. Glandular hair on the leaf. Oc. 4 Com. ; Ob. 3 mm. Ap.
131. Stoma on the lower surface of the leaf.
Oc. 4 Com. ; Ob. 3 mm. Ap. 132-134. Cucumis Melo.
132. Lower portion of the hair on the axis removed by peeling off the epidermis.
Oc. 2 Com. ; Ob. 8 mm. Ap.
133. Terminal portion of the same bair.
Oc. 2 Com. ; Ob. 8 mm. Ap.
134. Hair on the leaf.
Oc. 6 Com. ; 8 mm. Ap. 135-136. Citrullus Colocynthis.
135. T. S. of the axis.
Oc. 2. Com. ; Ob. 16 mm. Ap.
136. T. S. of the axis showing the ribs.
Oc 2 Com.; Ob. 3 mm. Ap. 137-138. Melothria maderaspatana
137. Hair on the leaf.
Oc. 2 Com. ; Ob. 8 mm. Ap.
138. Stoma on the axis.
Oc. 6 Com. ; Ob. 3 mm. Ap. 139-140. Trianthema triquetra.
139. T. S. of the leaf represent- ing half of the leaf-blade including the mid-rib.
Oc. 4 Com. ; Ob. 8 mm. Ap.
140. T. S. of the axis.
Oc. 6 Com. ; Ob. 8 mm. Ap<
(Upload an image to replace this placeholder.)
Plate XVI
141-143. Trianthema Pentandra.
141. T. S. of the leaf.
Oc. 2 Com. ; Ob. 3 mm. Ap.
142. T. S. of the leaf showing the enlarged epidermal cells. Oc. 6 Com. ; Ob. 8 mm. Ap.
143. T. S. of the axis.
Oc. 6 Com. ; Ob. 8 mm. Ap. 144-147. Orygia decumbens.
144. T. S, of the leaf.
Oc. 6 Com. ; Ob. 8 mm. Ap.
145. Stoma on the axis.
Oc. 6 Com. ; Ob. 3 mm. Ap.
146. T. S. of the axis.
Oc. 6 Com. ; Ob. 8 mm. Ap.
147. Stoma on the leaf.
Oc. 6 Com. ; Ob. 3 mm. Ap. 148. Mollugo hirla. Hair on the axis. Oc. 4 Com. ; Ob. 8 mm. Ap.
(Upload an image to replace this placeholder.)
Plate XVII
149-150. Moling o hirta.
149. T. S. of the axis.
Oc. 6 Com. ; Ob. 8 mm. Ap.
150. T. S. of the leaf.
Oc. 2 Com. ; Ob. 3 mm. Ap. 151-153. Mollugo nudicaulis.
151. T. S. of the leaf between
the mid-rib and the mar- gin. Oc. 4 Com. ; Ob. 3 mm. Ap.
152. T. S. of the leaf near the margin.
Oc. 4 Com. ; Ob. 3 mm. Ap.
153. T. S. of the axis.
Oc. 4 Com. ; Ob. 8 mm. Ap. 154-155. Mollugo Cerviana.
154. T. S. of the leaf represent- ing half the leaf-blade including the midrib.
Oc. 6 Com.; Ob. 8 mm. Ap.
155. T. S. of the axis represent- ing half the axis.
Oc. 2 Com.; Ob. 3 mm. Ap.
(Upload an image to replace this placeholder.)
Plate XVIII.
156. Gisehia pharnaceoides.
T. S. of the axis.
Oc. 4 Com, ; Ob. 8 mm. Ap. 157-159. Limeum indicuvi.
157. T. S.of the leaf.
Oc. 6 Com. ; Ob. 8 mm. Ap.
158. Stoma on the leaf.
Oc. 4 Com. ; Ob. 3 mm. Ap.
159. T. S. of the axis.
Oc. 4 Com. ; Ob. 8 mm. Ap. 160-161, Spermacoce hispida.
160. T. S. of the leaf.
Oc. 4 Com. ; Ob. 3 mm. Ap«
161. T. S. of the axis showing the wing-like rib bearing hairs.
Oc. 6 Com. ; Ob. 8 mm. Ap.
162. Oldenlandia aspera.
T. S. of the axis showing the dome-like hairy outgrowth Oc. 4 Com. Ob. ; 3 mm. Ap.
(Upload an image to replace this placeholder.)