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Transactions. 



In the leaf there are 3 larger veins and 2 very small ones. They are 

 surrounded by a sheath of small thin-walled parenchymatous cells, which 

 contain only a small number of chloroplasts. Below each bundle there 

 is an oil-duct, surrounded by 6-8 small epithelial cells. The amount 

 of lignified tissue in the bundle is small. 



Peduncle (figs. 12 and 13). — Fig. 12 gives a schematic view of the 

 transverse section. In each ridge there is a group of lignified cells, and 

 the whole of the central part is lignified. Fig. 13 shows the structure in 

 detail. 



Fig. 13. — Animtunie filifolium. Transverse section of peduncle ( X 175). m, cuticle; 

 6, stoma ; c, chlorenehyma ; d, oil-duct ; e, aqueous tissue ; /, pericycle 

 fibres ; g, phloem ; h, cambium ; i, xylem ; j. pith. 



The epidermis consists of small cells, which are squarish above the ridges 

 and are rectangular or oval in the furrows. The walls of these cells are 

 thickened and lignified, and there is a cuticle. Stomates are found in the 

 furrows. They are level with the epidermis ; the guard-cells have thickened 

 walls, and the opening is protected by guard-cell ridges. 



Beneath the epidermis in the ridges there is a mass of sclerenchyma : 

 this is composed of small cells with very thick walls and small lumen. Under 

 the epidermis in the furrows are about 5 rows of chlorenchymatous cells. 

 This band is also present under the sclerenchyma in the ridges ; here it is 

 about 2 cells wide. The outermost layer of this band of tissue consists 

 of cells which are slightly elongated in a direction parallel with the surface, 

 and which have slightly thickened walls. The rest of the chlorenchymatous 

 tissue consists of more or less rounded cells with thinner walls. This 

 tissue is vexy compact. 



