218 SCIENCE OF THE STUDY OF TREES. PART Ik 
think all aboriginal species must be decidedly distinct, so we think it practi- 
cable to render this distinctness so obvious, in the few words which constitute 
a specific character, that the name of a plant may be discovered by it. To 
recur to the genera Fraxinus and Cratzgus, we will ask any botanist, either 
practical or theoretical, whether, from the specific characters of the botanical 
species of F’, americana or of C. Oxyacantha, he could discover the individuals 
to which those names are intended to apply, without having recourse to dried 
specimens or engravings? We ask the same question with reference to most 
of the alleged species of Salix, U’lmus, Quércus, Pinus, and Ribus. We 
admit that many of these botanical species, or varieties as we consider them, 
may be made out from lengthened descriptions; but we deny the practicability 
of doing this, in many cases, from short specific characters. That we may not 
be misunderstood, we refer more particularly to the genera Quércus, Salix, 
U’\mus, and Rubus; and even to T'flia. 
But, though we question the utility of specific characters to botanical species 
as such, we are of opinion that they may be of some use when applied to these 
species, as being varieties of an aboriginal species, and indicating that they are 
such. For example, in the case of the specific character of Fraxinus 
pubéscens, caroliniana, lancea, &c., as absolute species, and to be compared 
with different botanical species of the same aboriginal species, and also of 
F. excélsior, we think it would be extremely difficult, if not impossible, to 
apply them ; but, if it were known that these botanical species were only 
varieties of F’. americana, the difficulties of distinguishing them would be 
greatly diminished. For this reason we shall, in many cases, adopt the specific 
characters of botanical species given by botanists, adding to them such de- 
scriptive particulars as our own observation has enabled us to supply. 
We may here refer to two causes, which have not only contributed to the 
great imperfection of the specific characters of botanical species; but which 
have been the means of multiplying the number and descriptions of these spe- 
cies in books, to an extent which, we are persuaded, does not exist in nature, 
One of the practices to which we allude is, that of describing species from dried 
specimens only ; and the other, that of mistaking varieties for species by col- 
lectors. We admit that the first of these practices is unavoidable in the infant 
state of botanical science; and that it must necessarily be continued, till 
botanists shall rise up in every country in such numbers, and of such acquire- 
ments, as to be able to describe the plants of every country from nature; or 
till all the species, or all the alleged species, of every genus of plants shall be 
assembled together in one spot, and what are really aboriginal species shall be 
determined, after observing them for a series of years. Happily, both these 
results are in progress of attainment: botanists are beginning to spring up 
in every civilised country, or to emigrate from old, and settle in newly dis- 
-covered countries ; and, in all the wealthiest governments of Europe, assem- 
blages of plants are being made in botanic gardens. If the directors of 
these gardens were to cooperate, and each to undertake the collection and 
the study of one or more genera of hardy plants, we should, at no distant 
period, be able to say what are really species, and what are not. If botanic 
gardens were established in every country and climate of the world, and the 
whole of the directors of these gardens were to act in concert (which concert, 
being quite distinct from political associations, would not be objected to by 
any government), in each garden might be assembled all the alleged species or 
varieties of at least two or three genera, those being selected for which its 
climate, situation, soil, and extent were most suitable; and, after a few years, 
the aboriginal species, and the more prominent varieties, might be determined 
on. Inthe meantime, this process might be commenced in many of the 
botanic gardens already established in the temperate regions of the world; and 
we have already shown (p. 192.) how, in every country in these regions, the 
determination of species, and their nomenclature, might be effected, as far as 
respects hardy trees and shrubs. 
When the natural system of botany comes to be more generally understood 
