144 Gibson. — Contributions towards a Knowledge of 
basal lobes. Stomata occur on the aligular face only, the guard-cells 
of which are very frequently folded outwards into the adjacent 
epidermal cells (Fig. 8). 
Dorsal leaf. Oblique hastate, with backwardly directed basal lobes 
and numerous multicellular hairs. Stomata occur on the aligular 
face only. 
Section. As in S. delicatissima. 
41. S. delicatissima, A. Br. (Fig. 18.) 
Ventral leaf Ovate oblique, with warty and spiny marginal cells 
not sclerotic. Stomata occur between the spines along the margin 
and on the aligular face, but not on the ligular side. 
The dorsal leaf is similar in shape, and stomata occur over the 
midrib and outside edge. 
Section. The ligular surface (of the ventral leaf) consists of large 
cells, tabular in section, followed by an ill-defined layer of peg-shaped 
cells with one to three chloroplastids in each, with their truncated 
ends continuous with long branched and reticulate mesophyll-cells, 
each with many small chloroplastids. The cuticle on both surfaces 
is very delicate (Fig. 18). 
42. S. sulcata, Spr. 
Ventral and dorsal leaves of this species are hastate, and bear well- 
marked basal lobes with a fringe of multicellular hairs. The margins 
of both leaves are smooth, or only faintly spiny. Stomata occur only 
on the aligular faces of the dorsal and ventral leaf. 
In section the pseudo-palisade-layer is absent, but the ligular 
epidermis is composed of cells resembling in section the peg-shaped 
polygonal based cells of the ligular epidermis in the leaves of the 
Martensii- type. 
43. S. Kraussiana, A. Br. 
Ventral leaf. Oblique, pointed, unequal-sided, with spiny margins 
and warty marginal cells. Numerous stomata occur on the margin 
and on the ligular surface near it, as well as over the midrib on the 
aligular face. 
Dorsal leaf Oblique, pointed, and unequal sided, in outline like that 
of a Begonia leaf. The margin has short spines. Marginal stomata 
occur on the ligular face, and also over the midrib on the aligular face. 
Section. As in S. delicatissima. 
