18 THE STORY OF PLANT LIFE 
When the perianth is of one kind it may resemble 
the calyx and be sepaloid, or the corolla and be 
petaloid. 
The stamens are made up of filaments bearing 
anthers with pollen sacs, with different ways of 
opening or dehiscence. 
The carpels consist of ovules, enclosed in an ovary, 
with a style bearing a stigma or receptive area for the 
pollen-grains. When the ovary contains one chamber 
or cell or loculus it is unilocular, when two, bilocular 
andso on. These terms explained serve in the place 
of a glossary. 
PLANTS AND THEIR POLLINATION. 
Considerable stress has been laid in the descrip- 
tion of the common types of each order in Chapters 
I to V upon the ways and means of pollination and 
seed dispersal, as being the two most interesting phe- 
nomena of plant-life and the most important in their 
life-history. 
Flowerless plants do not accomplish their sexual 
phase in the same way as flowering plants, but in 
the conjugation of the male and female elements 
one element—water—is necessary before the plant or 
its ovum is fertilised, and this element, though in a 
different way, plays a part in the pollination of 
flowers, but though it is common to both groups of 
plants, it is not probable that there was a passage 
from the fertilisation of the flowerless plants by 
