280 



growing fern-trees but only in our warmest valleys of richest 

 soil. The best temperature for Cinchonas is from 53° to 

 GQ Q F. ; but they mostly will endure in open places a mini- 

 mum of 32° F. ; in the brush shades of the Botanic Garden 

 of Melbourne, where years ago already Cinchonas were 

 raised by the thousands, they have even resisted uninjured 

 a temperatnre of a few degrees less, wherever the wind had 

 no access, while under such very slight cover the Cinchonas 

 withstood also a heat of a few degrees over 100° F. The 

 plants are most easily raised from seeds, best under some 

 cover such as mats and they are seeding copiously already 

 several years after planting. The contents of alkaloids in 

 the bark can be much increased by artificial treatment, if 

 the bark is only removed on one side of the stem and the 

 denuded part covered with moss, under which in one year 

 as much bark is formed as otherwise requires three years' 

 growth, such forced bark moreover containing the astound- 

 ing quantity of as much as 25 alkaloids, because no loss 

 of these precious substances takes place by gradual disin- 

 tegration through age. The Cinchona-plants are set out at 

 distances of about 6 feet. The harvest of bark begins in 

 the fourth or fifth year. The price varies in Europe from 

 2s. to 9s. per lb. according to quality. The limits assigned 

 to this small literary compilation, do not admit of entering 

 further into details on this occasion, but I may yet add, that 

 in the Darjeeling district over three millions of Cinchona 

 plants were in cultivation in 1869, raised in Government 

 plantations. 



Citrus Aurantium, L * 



The Orange (in the widest sense of the word). A native of 

 South Asia. A tree of longevity, known to have attained 

 an age of 600 years and more. Any specific differences, to 

 distinguish C. Aurantium from C. medica, if they once 

 existed, are obliterated now through hybridisation at least 

 iu the cultivated forms. As prominent varieties of C. 

 Aurantium may be distinguished : — 



Citrus Bigaraclia, Duhamel. The Bitter Orange. This fur- 

 nishes from its flowers the Neroli Oil so delicious and costly 



