LINDLEY’S NATURAL SYSTEM. 421 
Under these divisions Endlicher included 277 Natural Orders. 
After Jussieu, he commenced with the simplest plants and gra- 
dually proceeded to the more complicated, placing those of the 
Leguminosz at the highest point of the series. 
LinpDiey’s Naturat SysteEmM.—To Lindley especially belongs 
the merit of having been the first botanist who made any serious 
attempt to introduce a natural arrangement of plants into 
use in this country. The first system proposed by him in 1830 
was but aslight modification of that of De Candolle. Noattempt 
was made in this system to form minor groups or divisions of 
the tribes ; but in 1833, in a new system, Lindley arranged the 
natural orders in groups subordinate to the higher divisions, 
which were called Nixus (tendencies). These primary divisions 
were again divided into Sub-classes, Cohorts, and Nixus or 
eroups of nearly allied Natural Orders. In 1838, Lindley again 
altered his arrangement so far as regarded Exogens; and finally, 
in the year 1845, further modified his views, and proposed the 
following scheme, which was that adopted by him in his great 
work on ‘The Veyetable Kingdom.’ 
LINDLEY’S NATURAL SYSTEM. 
' 1. ASEXUAL, OR FLOWERLESS PLANTs. 
Stem and leaves undistinguishable . Class 1. Thallogens. 
Stem and leaves distinguishable . . Class 2. Acrogens. 
2. SExvAL, OR FLOWERING PLANTS. 
Fructification springing from a thallus Class 3. Rhizogens. 
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 : : . Class 4. Endogens. 
Leaves net-veined, deciduous ; 
wood of the stem, when peren- 
nial, arranged in a circle with 
a central pith ‘ : . Class 5. Dictyogens. 
Wood of stem youngest at the circum- 
ference, always concentric; co- 
tyledons two or more. 
Seeds quite naked . : . Class 6. Gymnogens. 
Seeds enclosed in seed vessels . Class 7. Exogens. 
The Exogens were further divided into four sub-classes 
thus :— 
Sub-class 1. Diclinous Exogens, or those with unisexual flowers, 
and without any customary tendency to form 
hermaphrodite flowers. 
