( vi ) 
Briefly, the plants are arranged under three main classes as 
follows : — 
Class I— Plants which begin to grow from seeds by sending up 
two very simple leaves called cotyledons, and which therefore 
are called Dicotyledons. As full-grown plants they may 
usually be recognised by having mature leaves with branched 
or net-like veins, and flowers with their parts not in threes or 
multiples of three. 
This class is represented in plates 1-52, grouped as 
follows : — 
1-23 — in which the petals are separate, not united, called 
Polypetalse ; 
24-48— in which the petals are more or less united, some in 
a tube, others only near the base, called Monopetalae ; 
49_52— in which the flowers are incomplete, Incomplete.. 
Class II.— Plants which begin to grow from seeds by sending up 
one very simple leaf 'cotyledon,' and which are called 
Monocotyledons. As full-grown plants they may usually be 
recognised by having mature leaves with parallel veins, and 
flowers with their parts in threes or multiples of three ; repre- 
sented in plates 53-58. 
Class III.— Plants without true flowers and seeds, of which only 
ferns are included in this book; represented in plates 69-64. 
Within these classes and their subdivisions are arranged the 
Families of plants ; and these again are divided into Genera 
and Species. The botanical name of a plant is that of its 
genus and species. In the following Table of Contents the 
more important analytical characters which determine their 
arrangement have been added. 
