654 SYSTEMATIC BOTANY. 



Properties and TJses.—T'he species of Casuarina yield very 

 hard and heavy timber, and the bark of some is said to be tonic 

 and astringent. 



Casuarina. — Several species produce valuable timber, which is chiefly used 

 in this country for inlaying and marqueterie. The wood is known under 

 the names of Beef -wood, Botany Bay Oak, Forest Oak, He-Oak, She-Oak, &c. 

 The bark of C. murlcata is an excellent astringent, which is in use in India. 



Natural Order 232. Betulace.b. — The Birch Order. — 

 Character, — Trees or shrubs. Xmws simple, alternate, with 

 deciduous stipules. Flowers unisexual, amentaceous, with no 

 true calyx, but in its place they have small scaly bracts, 

 which in some cases are arranged in a whorled manner. 

 Male flowers with 2 or 3 stamens opposite the bracts. Female 

 flowers with a 2-celled ovary, and 1 pendulous ovule in each cell. 

 Fruit dry, indehiscent, 1 -celled, 1-seeded, without a cupule. Seed 

 pendulous, exalbuminous ; 7'adicle superior. 



Bistrihutmi, ^-e. — They are principally natives of the colder 

 regions in the northern hemisphere. Examples of the Genera: — 

 Betula, Alnus. These are the only genera ; there are about 70 

 species. 



Properties and Uses. — They are valuable for their timter, 

 and for their astringent tonic and febrifugal barks, 



Alnus.— -A. ghUinosa. the common Alder.— Its wood is valuable for the piles 

 of bridge?, and for other purposes where entire submersion in water or damp 

 earth is required. Its bark is astringent, and has been used in medicine, 

 and for tanning and dyeing. The leaves and catkins have similar properties. 

 The wood is also employed for making charcoal, which is much valued 

 for the manufacture of gunpowder. The bark of A. incana is used in 

 Kamtschatka for making a kind of bread. 



Betula. — B. alba, the common Bii-ch, yields the timber known as Norway 

 Birch. The wood is also used for charcoal. The bark yields a kind of oil, 

 which gives the ixjculiar odour to Russian leather. The sap contains in the 

 spring a good deal of sugar, hence it is then used in the preparation of a 

 kind of wine ; this is commonly known as Birch wine, and is employed in 

 domestic practice for those afflicted with stone or gi-avel, B. nigra.— Ihe 

 Black Birch of North America is also valuable for its timber. Its sap, like 

 that of B. alba and B. lenta, yields sugar of good quality, and wine may be 

 also prepared from it. B. papijracea has a thick tough bark, which is used 

 by the Indians in North Ainerica for boats, shoe-soles, and other purposes. 

 The bark of B. Bhajapallra is employed in India as a kind of paper. 

 The bark of B. lenta, known in the United States as Sweet Birch or Cherry 

 Birch, yields by distillation a volatile oil, which is identical with that of the 

 GauWieria procumbens. 



Natural Order 233, ALTiNGiACEiE or Liquidambaeace^. — The 

 Liquidambar Order. — Character. — Balsamiferous trees, with 

 simple or lobed alternate leaves, and deciduous stipules. Flowers 

 unisexual, involucrate, amentaceous. Male flowers naked, with 

 numerous nearly sessile anthers. Female flowers with a 2-celJed 

 ovary, the whole flowers collected into a globular head ; ovules 

 numerous. Fruit a cone-shaped body, composed of 2-celled 

 capsules enclosed in hard scales. Seeds winged, peltate, albu- 

 minous ; embryo inverted ; radicle superior. 



Distribution, ^c. — Natives of the warmer parts of India, North 



