feUCALVPTUS TEEES. 103 



precise quantity of tannic substance to be obtained 

 from saplings and foliage of various Eucajjpts, acacise 

 and casuarinse remains yet unascertained ; but it is 

 likely large enough to base on their yield of tannic 

 acid special forest industries. 



For belts of shelter-plantations, again, no country 

 in the warm temperate or subtropic zone could choose 

 trees of easier growth, greater resistance, rapidity of 

 increment, early and copious seeding, contentedness 

 with poor soil, and yet valuable.wood for various pur- 

 poses, than some of the Australian acacise and casua- 

 rinse. They exceed much in quickness of growth the 

 coast shelter-pines of South Europe, Pinus haleppen- 

 sis and Pinus pinaster, but are not all equally lasting. 

 The trade in seeds of this kind is also not unimpor- 

 tant, and the sources of it are, at least partly, in our 

 sylvan land. 



Still another forest industry might be viewed as 

 especially Australian, namely, the supply of Fern-trees 

 for commercial exportation. Though about one hun- 

 dred and fifty kinds of Fern-trees are now known, 

 they are mostly children of tropical or subtropical 

 countries, and these, again, nearly all restricted to the 

 humid jungles or the shady valleys meandered by for- 

 est brooks. Very few species of these noble plants 

 extend to a zone so cool as that of Victoria, Tasma- 

 nia, and New Zealand. Again, among this very lim- 

 ited number, the stout and large Dicksonia antartica 

 is not only one of the tallest of all the Fern-trees of 

 the globe, but certainly also the most hardy, and the 

 one which best of all endures a transit through great 

 distances. Indeed, a fresh, frondless stem, even if 

 weighing nearly half a ton, requires only to be placed, 



