30 THE STORY OF PLANT LIFE 
Brongniart, 1843, rejected the section Apetale, 
and he divided the Monocotyledons into two groups, 
according to the presence or absence of endosperm 
in the seeds. 
In the system adopted by Bentham and Hooker, 
1862 to 1883, the Dicotyledons are divided, following 
De Candolle largely, into Polypetale, Gamopetale, 
Monochlamydez. In the Polypetalez they include 
Thalamiflore, Disciflore in which a highly stamini- 
ferous disc occurs, and Calyciflore. 
The Gamopetalz are equivalent to the Corolli- 
flore. These are divided into Inferz with the ovary 
inferior, Heteromerze with the ovary superior, and 
Bicarpellate with the ovary superior and two 
‘carpels, whereas there are more than two in Hetero- 
mere. 
In Engler’s system, which is much used on the 
Continent, and more largely here now than formerly, 
the Monocotyledons are divided into ten cohorts and 
forty-seven natural orders. 
The Dicotyledons are divided into two series, 
Archichlamydez and Sympetale, thus producing con- 
siderable rearrangement of Bentham and Hooker’s 
system. 
Eichler, whose system has been emended by 
Warming, divides Monocotyledons into seven co- 
horts,and Dicotyledons into two series—Choripetale, 
which equals Archichlamydez, and Sympetale. 
The object of classification is to form an arrange- 
ment of plants on natural lines. It is not an aid to 
