LIST OF ILLUSTRATIONS, 7 
Figs. 4 and 5 (X500). — Epidermal layer of leaf — 58 
Fig. 6 (X175)— 58 
(a) apex of Fig. 2, with young leaves 
b b' enlarged, showing structure of 
epidermal layer. 
Plate XV. 
Fig. 7. — Cross section of blight free tuber after 20 
hours’ steeping in 10% H , So 4 and Methyl 
Orange. Entry of the acid is exclusively 
confined to the “ eyes ” of the tuber 70 
Fig. 8. — Cross section of a blight infested tuber 
after 20 hours’ steeping in 10% H, So. and 
Methyl Orange. Entry of the acid takes 
place through the “ eyes ” and also through 
those portions of the section which have 
been partially destroyed by the attack of 
the Blight fungus 70 
Plates XVI — XVII. 
Figs. 9 to 12. — Illustrating influence on growth 
exercised by various treatments of “ cut 
sets ” 73-74 
Nos. 1 and 5. — “ Sets ” treated with lime 
„ 2 and 6. — „ „ „ sulphur . . . 
„ 3 and 7. — ,, ,, ,, sand 
,, 4 and 8. — Untreated “ Sets ” (Controls) .... 
[N.B. — The arrows in these figures indicate 
the positions of the “ eves.”] 
Plate XVIII. Map of Western Australia showing 
the localities of the Rare Metals 
83 
