THE HIMALAYAN MOUNTAINS. 3 
that the space whence the several collections have been formed extends over ten 
degrees of latitude and nearly twenty of longitude. 
Though there is no intention, in the present work, of treating of the Botany of 
india in general, yet as it is proposed particularly to note, not only the difference in 
the vegetation of the Hills and of the Plains and the distribution of particular families, 
but also for what other plants, chiefly the useful products of similarly constituted 
countries, India is peculiarly adapted, it may not be improper to remark, that the 
observations respecting the distribution of different tribes will be deduced from the 
collections and works of Drs. Roxburgh and Buchanan, Wallich and Wight, as well 
as from the author’s own collections made in the most northern provinces of India. 
It is hardly necessary, after the liberality with which Dr. Wallich placed his 
treasures in the hands of the Botanical World, to mention, that previous to his 
departure for India he expressed his most anxious desire that every possible use 
should be made of that portion of his collection which he had not himself had an 
opportunity of publishing, and joined in an application to the Honourable the Court 
of Directors, that his unpublished drawings should be placed at the disposal of the 
author for the purpose of selections being made for the present work. Major-General 
Hardwicke has also most kindly placed in the author’s hands ten volumes of drawings 
made in the plains of Northern India, and also while travelling nearly thirty years 
ago in the Himalayas. These, when so used, will be duly acknowledged, but the 
greater portion of the illustrations will be from drawings made under the author’s 
own direction. These were executed by the Honourable Company’s painters, who 
during Dr. Wallich’s absence in England were by the orders of the then Governor- 
General of India, the Earl of Amherst, sent from the Botanic Garden at Calcutta 
to that of Saharunpore. 
Some explanation may perhaps be expected upon the preference given to the 
publication of the illustrations according to the natural families, as well as upon 
the particular series which has been adopted. For the latter no better reason than 
that of convenience can be assigned, as the celebrated De Candolle is the only bo- 
tanist who has attempted an arrangement of all plants according to their natural 
families. For the adoption of the natural method of classification, no apology is 
in the present day necessary, as the advantages have been so frequently displayed 
ever since the illustrious Mr. Brown proved them in his Prodromus of the Plants of 
New Holland, and has so often illustrated them by his luminous observations on 
the Flora of different countries; a course which has been followed by the great 
Humboldt and other celebrated botanists. For whether we consider the structure, 
classification, geographical distribution, properties, or uses of plants, in every way 
does the natural method afford numerous advantages, particularly as our observations, 
instead of being confined to species and genera, may in general be made applicable 
to whole tribes of plants. 
This we shall see to be more silken the case in noticing the geographical 
B 2 distribution 
