EXPLANATION OF THE PLATES. 
555 
PLATE TIL 
Fig. 1. A cluster of six-sided air-cells from the stem of Limnocharis Plumieri : 
they are formed entirely of prismatical cells ; a a, partitions dividing the air- 
cells in two. 
JFig. 2. A partition or diaphragm of the last-mentioned plant, showing the open 
passages that exist at the angles of the cells. When dry the rims of the 
passages are dark, as at a ; when immersed in water, the dark rim disappears, 
and the whole partition has the uniform appearance of b. 
Fig. 3. A portion of tlie cuticle, and a stoma, of the leaf of Oncidium altissimum ; 
a, the stoma, formed of two parallel glands or cells, which open by curving 
outwards. In this plant the stomata are very minute and few : on the mem- 
brane of each mesh of the cuticle are found sticking from four to six spherical 
semi-transparent green globules. 
Fig' 4. Stomata of Strobilanthes Sabiniana. They are very large, and crowded 
together in an irregular manner. 
Fig. 5. Ditto of Croton variegatum : this is an instance of a cuticle with sinuous 
lines. The orifice of each stoma is closed up with brownish matter. 
Fig. 6. A stoma of Canna iridiflora. 
Fig. 7. A cavity beneath the cuticle, in the parenchyma of Begonia sanguinea; 
seen from the inside, so that the cuticle is farthest from the eye. It is divided 
by sub-cylindrical cellules into five spaces, in each of which there lies a 
stoma. 
Fig. 8. One of the stomata of the same, more magnified, and showing that the 
medial line does not touch either end, and that the cavity of the stoma is filled 
with granular matter. 
Fig. 9. Stomata of the under side of the leaf of Caladium esculentum, with a 
portion of cuticle. These appear to be somewhat angular cellules, occupying 
the centre of every area of the cuticle. The stoma consists of an oval space, 
in the centre of which is a narrow cleft, with a border distinctly coloured 
orange or brownish, and having no communication with the circumference : 
the space between the cleft and the latter filled with a pale green granular 
substance. The cleft is sometimes seen closed, as at a, and then there is 
scarcely any appearance of a border. 
J'tV. 10. Cuticle and stomata of Yucca gloriosa : the latter lie in square areolae, 
and consist of two parallelograms lying parallel with each other. Small sphe- 
roidal bodies, having a luminous appearance under the microscope, stick here 
and there to the inside of the cuticle. 
Fig. 11. Stomata of Limnocharis Plumieri. These also lie in square areolae, 
but they have the ordinary structure : they are found in different degrees of 
openness, or even quite closed, upon a small piece of the same specimen. 
Fig. 12. Stamen of Lernna trisulca : anther bursting vertically. 
Fig. 13. Stamen of Polygonum Convolvulus; a, seen in front; b, from behind; 
c, the connectivum of the anther. 
Fig. 14. Stamen of Correa alba ; a, seen in front; b, from behind. 
Fig. 15. Stamen of Stachys sylvatica; a, filament; b, connectivum; c, anther, 
its lobes separated at the base by the connectivum. 
Fig. 16. Anther of Alchemilla arvensis ; one-celled, and bursting transversely. 
Fig. 17. Stamen of Scrophularia chrysanthemifolia ; a, part of the filament, and 
