132 Gibson . — Contributions towards a Know ledge of 
polygonal, becoming longer towards the margins. The stomata are 
surrounded by irregularly thickened cells. 
Section . As in the type. 
5. S. erythropus, Spr. 
Ventral leaf. Ovate, oblique, curved, with numerous marginal 
trichomata with red contents. Stomata occur near the base on the 
outer region of the ligular epidermis. The elongated cells of the 
aligular face are not wavy, the cells near the , stomata becoming 
polygonal. 
Dorsal leaf. Similar in form to the ventral leaf, but with a long 
cusp. The ligular face bears numerous stomata distributed over the 
outside half of the leaf. The marginal cells are sclerotic and warty. 
The cells of the aligular face are long at the margins, shorter near the 
midrib where the stomata occur. 
Section. The cells composing the reticulum are shorter and more 
rounded than in the four preceding species. 
6. S. eauleseens, Spr. 
Ventral leaf. Ovate, curved, pointed, with marginal unicellular 
spines. Stomata occur near the base of the ligular face of the leaf. 
The cells of the aligular surface are elongated, but not wavy, though 
warty. The aligular face bears numerous stomata. 
Dorsal leaf. Similar in form to the ventral leaf, but with a longer 
cusp. Stomata occur on the aligular face only. 
Section. As in the type. 
In var. argentea there are no stomata on the ligular surface of the 
ventral leaf. In var. japonica and var. minor the ligular surface of 
the ventral leaf has stomata near the base, and the epidermal cells are 
elongated on one side of the midrib and polygonal on the other. On 
the aligular face of the dorsal leaf in these varieties a few sclerotic cells 
occur on either side of the midrib. I draw attention to these small 
histological differences by way of emphasizing the great variation that 
occurs in the leaf-characters. 
7. S. Griffiths, Spr. 
Ventral leaf Unequal-sided, awl-shaped, pointed, spiny. Marginal 
sclerotic warty cells on the gibbous side. A few stomata occur on the 
ligular face near the margin of the leaf. Numerous stomata and 
sclerotic fibres on the aligular surface. 
