308 
LINDLEY'S VEGETABLE KINGDOM. 
placed in the Bignonial Alliance because of 
their intimate relation to Figworts, no apparent 
means remain of clearly denning what is meant 
by the Bignonial Alliance. If, on the other 
hand. Figworts are stationed in the Solanal 
Alliance, then the distinctive characters of that 
Alliance are also rendered obscure and difficult, 
or impossible of application. But place Night- 
shades in the Solanal, and Figworts in the 
Bignonial Alliance, and the language of Bo- 
tanists affords as clear a discrimination as can 
be wished for. And so of other cases. Indeed, 
1 am so persuaded of this, that in my opinion 
all instances of confused and vague characters 
are only so many proofs of Botanists not 
having clearly understood the plants that they 
have endeavoured to classify. 
"It will, perhaps, be alleged that the doctrine 
just inculcated is directly opposed to the first 
principles of a Natural System : but such is 
not the case. No absolute limits, in fact, exist, 
by which groups of plants can be circum- 
scribed. They pass into each other by insensi- 
ble gradations, and every group has apparently 
some species which assumes in part the struc- 
ture of some other group. Two countries are 
separated by a river whose waters are common 
to both banks : in a geographical division of 
territory the river may be assigned to either 
the left bank or the right bank, but such an 
arrangement is arbitrary ; and yet the interior 
of the countries is unaffected by it. So with 
the groups of plants ; it cannot be of any 
possible consequence whether an intermediate 
or frontier plant be assigned to one group or 
another, and convenience alone should be 
considered in such a matter. This long since 
led me to offer the following observations, the 
justice of which, much more experience entirely 
confirms : — 'All the groups into which plants 
are thrown are in one sense artificial, inasmuch 
as Nature recognises no such groups. Never- 
theless, consisting in all cases of species very 
closely allied in nature, they are in another 
sense natural. But as the Classes, Sub-classes, 
Alliances, Natural Orders, and Genera of 
Botanists, have no real existence in nature, it 
follows that they have no fixed limits, and con- 
sequently that it is impossible to define them. 
They are to be considered as nothing more 
than the expression of particular ienclencies 
(nixus), on the part of the plants they compre- 
hend, to assume a particular mode of develop- 
ment. Their characters are only a declaration 
of their prevailing tendencies.'"- — P.xxix. xxx. 
Professor Lindley proceeds to give an out- 
line of all the Natural Systems. Those of John 
Ray, 1703, Linna?us, 1751, Jussieu, 1789, 
Brown, 1810, De Candolle, 1813, Agardh, 
1825, Perleb, 1826, Dumortier, 1827, Bart- 
ling, 1830, John Lindley, 1830, Hess, 1832, 
Schultz, 1832, John Lindley, 1833, Horaninow, 
1834, Fries, 1835, Martius, 1835, Bromhead, 
1836, John Lindley, 1836, Endlicher, 1836- 
1840, John Lindley, 1838, Perleb, 1838, John 
Lindley, 1839, Baskerville, 1839, Trautvetter, 
1841, Brongniart, 1843, Meisner, 1843, Ho- 
raninow, 1843, Jussieu, jun. 1844, John 
Lindley, 1845, which is the present work. 
In this list the same authors appear when 
they have made any alterations in their pre- 
vious works. The arrangements of them all 
differ in some particulars, and an analysis of 
their several arrangements shows, at least, that 
while Linnaeus' artificial arrangement is allow- 
ed to remain as it was, the Natural Systems 
have been not only revived by different authors, 
but they have undergone many changes by the 
writers themselves, who, as new objects and 
new facts were developed, saw good reason, 
we presume, for the variations they have made 
from time to time. It is but fair to say, that 
among all these systems, Professor Lindley 
has, in this last arrangement, done all that 
can, at present, be done, to advance in what, 
at present, appears a right path. The system 
employed in the present volume is more com- 
prehensive than any of its predecessors. It is 
altogether different from his own arrangement 
of 1833, in Nixus Plantarum. The classes 
in which were : — 
CLASSES. 
( I. Exogenj:. Angiosperm*. 
fVasculares ] II. Exogen^.Gymnospermj;. 
Sexuales (.III. Endogen/e. 
(. Evasculares IV. Rhizanthe^;. 
V. EsEXUALLS. 
The classes in the present volume amount 
to seven, and are given as under : — 
CLASSES. 
Asexual or Flowerless Plants. 
Stems and leaves undistinguishable I. Thallogens. 
Stems and leaves distinguishable- II. Acrogens. 
Sexual or Flowering Plants. 
Fructification springing from a 
thallus ----- III. Riiizogens. 
Fructification springing from a stem 
Wood of stem youngest in the centre ; cotyledon single. 
Leaves parallel-veined, perma- 
nent ; wood of the stem always 
confused - IV. Endogens. 
Leaves net-veined, deciduous; 
wood of the stem, when per- 
ennial, arranged in a circle 
with a central pith - - V. Dictyogens. 
Wood of stem youngest at the circumference, 
always concentric ; cotyledons two or more. 
Seeds quite naked - - - VI. Gymnogf.ns. 
Seeds enclosed in seed-vessels - VII. Exogens. 
The ramifications are as important ; they are 
carried out to fifty-six Alliances, and three 
hundred and three Natural Orders : each of 
these is described with great precision, and 
are again broken into Sections, or Tribes, or 
Sub-orders ; and every leading subject is beau- 
tifully illustrated, some, it is true, with engrav- 
ings, which we must not respect the less for 
