26 THE TRANSVERSE SECTIONS OF PETIOLES OP EUCALYPTS 



5. E. marginata, Donu ; Jarrah. 

 Tree, averaging 100ft. in height. 

 Leaves. — Somewhat paler beneath. 

 Size of Section. — About 1 hne broad b}' i Una thick, or fully tw^ice as broad as 



thick. 

 Outline of Section. Laterally elongated, ovoid usually. 

 Epidermis. — Thickness, 5^ — 4 ^°- 



Breadth, ^1 — ji^ in. 

 Cortical Cavities. — 3^5 ^^i-' aliiiost round, numbering from 9 to 3. 

 Crystals. — Numerous. 



Hard Bast. — More or less continuous, and generally one or a few cells thick. 

 Wood-curve (see Fig. 15). — Elongated laterally and slender, sometimes slightly 

 thickened about the middle, incurving somewhat sharply, and horns 

 usually relatively short. 

 Vessels. — Largest, j^in. 



Average, about half that. 



Medium-sized, moderately numerous, and distributed pretty regularly. 



Characteristic features : 



Section. — Fully twice as broad as thick. 



Cortical Cavities. — Moderately large and numerous. 



Hard Bast. — Continuous ; a few cehs thick. 



Wood-curve. — With slender, elongated body, and usually short slender 



horns. 

 Vessels.— Medium-sized, moderately numerous, and regularly distributed. 



6. E. diversicolor, F. v. M.; Karri. 



Tree. — Very tall and straight. 



Leaves. — Elongated, much paler beneath. 



Size of Section. — About | line broad by J line thick, or about IJ times broader 



than thick. 

 Outline of Section. — Oval to round, usually flattened on upper surface. 

 Epidermis. — Thickness, g^ in. 



Breadth, about half the thickness. 

 Cortical Cavities. — ^ in., roundish, numbering from 7 to 2, or sometimes none. 

 Crystals. — Few. 

 Hard Bast. — Poorly developed, very discontinuous, often consisting merely of 



single isolated cells. 

 Wood-curve (see Fig. 16). — Body may be either short and stout, or elongated 



and slender, with gentle incurving and somewhat stoutish horns. 



