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DOMESTIC BOTANY. 



New Zealand Flax {Phormium tenax). A distinct plant, 

 with smooth, sword-shaped leaves, 4 — 6 feet long, of a firm 

 texture and abounding in stout fibre. The flowers are red, 

 borne on a scape in panicles. Scape 10 or even more feet in 

 height. In New Zealand it occupies large tracts of the 

 country, and is used by the natives for making ropes, mats, &c. 

 Large quantities have been imported to this country. It is 

 tolerably hardy, and about fifty years ago a company was 

 established for its cultivation in the South of Ireland, but its 

 slow growth caused it to be abandoned. 



Grass Gum Trees (Xanthorrhoea). This remarkable genus 

 consists of 9 or 10 species, natives of Australia. They hold 

 the same position in Liliacese as Kingia does in Juncaceae. 

 Stems cylindrical, formed by the broad bases of grass-like 

 leaves, and attaining a foot or more in diameter. X. arhorea 

 and X. quadrangularis attain the height of 6 — 10 feet, and the 

 flower- stem springs like a stout rod from the centre of the 

 crown of leaves, and frequently is 10 — 20 feet long, the upper 

 part being densely covered with small yellowish-white flowers. 

 The leaves are often burnt by the grass-fires, leaving the 

 blackened stems standing, which at a distance have the ap- 

 pearance of black men, from which circumstance the name 

 " Black boy trees" has been applied to them. The smaller 

 species look like thatched beehives. They yield a fragrant 

 resin of two kinds, called " Black Boy" and " Botany Bay" 

 Gum, and contain abundance of Picric acid, which is exten- 

 sively used in the preparation of the highly explosive com- 

 pound, " Picrate of Potassium." This acid is used for dyeing 

 silk and wool, and imparts to them a yellow colour. The 

 gum resin is made into candles, and is used in some Roman 

 Catholic churches as incense. 



These plants are of very slow growth, it requiring many 

 years before they produce a stem, as shown by an example 

 of a plant at Kew thirty years old and still stemless. 



