GUM-TREES OF AUSTRALIA. 423 



extent. In fact, they may be more correctly described as enormous 

 thickets scattered in tolerably sheltered localities. Most of the trees 

 which compose them have trunks of great feebleness compared with 

 their height, which is often prodigious, and they do not begin to 

 ramify until near their summits. Their bark is smooth, and usually 

 of a grayish- white. Of all their species it can only be said that two 

 the Stadmannia austral and the Alectryon bear fruit which men can 

 eat even under the pressure of hunger. Finally and this without 

 doubt is the most singular feature of a truly exceptional vegetation 

 while all the trees and herbaceous plants of the Old and New Worlds 

 develop their leaves horizontally, or on a plane tangent to the cylin- 

 drical surface of the trunk or stem, in Australia the leaves of the trees 

 are disposed vertically ; in such wise that they give scarcely any 

 shade, and yet are themselves exposed in the very slightest degree to 

 the action of the solar rays. It is owing to this latter circumstance 

 they are always weakly coloured ; and thus they give to the densest 

 forests and the most robust trees a sickly tint, a sort of pallor of disease, 

 which saddens the gaze accustomed to the varied tones and vivid 

 hues of the verdure of tropical forests, or to the bold contrasts of light 

 and shade exhibited by the woods of Europe and North America. 



The Australian species are comprised in a small number of families, 

 notably in those of the Coniferse and Myrtaceas. Certain forests are 

 wholly composed of Casuarinas ; others, of Acacias ; others again, of 

 Eucalypti. Some of the latter trees may be ranged among the greatest 

 with which botanists are acquainted. The Blue Gum (Eucalyptus 

 globulus] attains, for instance, the extraordinary stature of upwards 

 of 300 feet, and does not send out a single branch until half this dis- 

 tance from the ground. Its upright cylindrical trunk furnishes a 

 timber much appreciated by ship-wrights, and especially makes ad- 

 mirable masts. The Eucalypti secrete in abundance a white, sugary, 

 and aromatic substance ; whence they derive their popular name of 

 " gum trees" a name which is also bestowed very frequently upon 

 the gum-bearing Acacias. 



The family of Conifers exhibit themselves in Australia, like every 



