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Transactions. 



Fig. 3 gives the epidermis from a longitudinal section ; from this it will be 

 seen that the stomates are at the same level as the epidermal cells, and the 

 opening is protected by guard-cell ridges. 



The cortex is composed of closely packed more or less polygonal cells 

 with thin walls. In the outer part of the cortex, and especially in the 



Fig. 2. — Exocarpus Bidwillii. Diagrammatic transverse section of the stem ( x 24). 



a, thick cuticle ; b, furrow lined with hairs ; c, pericycle fibres. 



Fig. 3. — Exocarpus Bidwillii. Longitudinal section through epidermis ( X 350). a, guard- 

 cell ridge. 

 Fig. 4. — Exocarpus Bidwillii. Transverse section of stem (x 120). a, thick cuticle: 



b, tannin-containing cells ; c, chlorenchyma ; d, pericycle fibres ; e, phloem : 

 /, vessels of xylem ; <j, lignified pith. 



ridges, the cortical cells contain tannin : in the inner part of the cortex 

 most of the cells contain numerous chloroplasts, but some contain tannin. 

 At intervals there are large groups of pericycle fibres, composed of small 

 cells with very thick lignified walls and small lumen. 



