AS AIDS IN THE DETERMINATION OF SPECIES. 41 



Cbaracteristic features : 



Section. — Exceptionally small, equally broad and thick. 



Cortical Cavities. — Small. 



Hard Bast. — Composed of few cells, but strongly tbickened. 



Wood-curve. — Always found entire, witb excessively stout body and short, 



stout horns. 

 Vessels. — Small, moderately numerous, and pretty regularly distributed. 



Eemaeks. — In proportion to the size of the section, the wood-curve is the 

 thickest of any yet investigated. This is of interest in connection with such a very 

 tall tree, since the water must be raised so great a distance to reach the topmost 

 boughs. It was also observed that the leaves from this tree did not, in the least, 

 discolour the water in wbich they were kept for some months, although all other 

 species examined did so, more or less. 



26. E. viminalis, Labillardiere ; Manna-Eucalypt. 



Tree. — Tall, and sometimes even gigantic. 



Leaves. — Thin, equally green on both sides. 



Size of Section. — Either 1 line broad by | line thick, or of equal breadth and 



thickness. 

 Outline of Section. ^ — Koimd to egg-shaped, or flattened on top, so as to become 



somewhat hemispherical. 

 Epidermis.— Thickness, ^^ in. 



Breadth, as broad as thick, and sometimes broader. 

 Cortical Cavities.— j^ in. in some sections, and only half that in others; 

 roundish to oval ; numbering from 7, often 2, and sometimes absent. 

 Crystals.- — Numerous, and sometimes large. 

 Hard Bast. — Moderately developed ; slightly discontinuous ; 1 sometimes, 



but mostly several cells thick. 

 Wood-curve (see Figs. 36 and y6«). — Body straight and thickened, with short, 

 sharply incurved, and usually broken horns. Occasionally a distinct 

 isolated bundle at side of one of the horns. 

 Vessels. — Largest, from ^ — ^ in. 

 Average.— ^3V„ in. 



Small, comparatively few or moderately numerous, mostly distributed 

 towards upper portion of wood, and generally absent irom horns. 

 Characteristic features : 



Section. — Average size. 



Epidermis. — Relatively thin, composed of cells at least as broad as thick. 



Cortical Cavities. — Medium size, often few. 



