280 
growing fern-trees but only in our warmest valleys of richest 
soil. The best temperature for Cinchonas is from 53° to 
66° T. ; but they mostly will endure in open places a mini- 
mum of 32° r. ; in the brush shades of the Botanic Glarden 
of Melbourne, where years ago already Cinchonas were 
raised by the thousands, they have even resisted uninjured 
a temperature 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° B. 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 wmre in cultivation in 1869, raised in Government 
plantations. 
Citrus Aurantium, E.* 
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 
in the cultivated forms. As prominent varieties of C. 
Aurantium may be distinguished : — 
Citrus Bigaradia, Duhamel. The Bitter Orange. This fur- 
nishes from its floAvers the Neroli Oil so delicious and costly 
