Naturalisation in Extra-Tropical Countries. 3 



Acacia Catechu, Willdenow. 



India to East- Africa, up to 5,000 feet. A tree, attaining 80 feet in 

 height with a stem-circumference of 9 feet. Will bear some frost 

 [Brandis]. Wood hard, heavy, extremely durable, locally chosen for 

 underground-posts particularly and mill-work. The extract, prepared 

 from the bark and heart-wood, is one of the catechus of medicine 

 or cutch of tannery. Pure cutch is worth about 25 per ton ; 4 tons 

 of bark will produce 1 ton of cutch. The tree also yields a gum 

 which is superior to that of A. Arabica [Dr. G. Watt]. A. Suma 

 (Kurz) is closely allied. The two other principal kinds of catechu 

 are tropical products from Areca Catechu and Nauclea Gambir, that 

 of the latter being obtained from some congeners also. The import 

 of cutch aud gambir into the United Kingdom during 1886 was 

 28,352 tons, valued at 654.218. 



Acacia Cavenia, Bertero. 



The " Espino " of the present inhabitants of Chili, the " Cavan " 

 of the former population. A small tree with exceedingly hard 

 wood, resisting underground moisture. The plant is well adapted 

 for hedges. The husks contain 32 per dent, tannin [Sievers], 

 particularly valuable as a dye-material. 



Acacia concinna, De Candolle. 



India, China. Praised by Dr. Cleghorn as a valuable hedge- 

 shrub. The pod contains saponin. 



Acacia cyclopis, Cunningham. 



South- Western Australia. A tall shrub, delighting in coast-sands, 

 but allied to A. Melanoxylon, to which it stands almost in the same 

 relation as A. Sophorae to A. longifolia. According to Mr. A. W. 

 Heywood it has been utilised in South- Africa for fixing drift-sand on 

 sea-shores. 



Acacia dealbata, Link. 



South-Eastern Australia and Tasmania. This tree is generally 

 known amongst Australian colonists as Silver- Wattle. It prefers 

 for its habitation humid river-banks, and sometimes attains there a 

 height of 150 feet, supplying a clear and tough timber, used by 

 coopers and other artisans, but principally serving as select fuel of 

 great heating power. From the thinly-split wood elegant baskets 

 can be made. The bark of this tree is thinner and inferior in 

 quality to that of the Black Wattle, yielding generally much less 

 quantity of tannin-principle. Mr. J. H. Maiden determined the 

 average proportion of mimosa-tannic acid in absolutely dry bark as 

 21-22 against 30-08 of A. mollissima. He relies on the colour- 

 reaction, given by a drop of concentrated sulphuric acid, as the 

 most valuable for roughly ascertaining the strength of tan-samples ; 

 that from the rich wattle barks gives rose-madder colour, and all 



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