ORIGIN OF LIFE 15 
where we could not for an instant survive, to pro- 
duce beings we should not, without a special educa- 
tion, recognize as being alive like ourselves.” 
It is generally conceded that life on our globe 
began in the water, and thence spread to the land. 
Very significant in this regard is the fact that all but 
the highest plants require the presence of external 
water for the act of fertilization, as the male cell 
swims through water to the ovum. Only the most 
recently evolved groups have shaken off this ancestral 
trait; and as regards the whole economy of plants 
the water relation remains, throughout the entire 
vegetable kingdom, the most obvious and universally 
important of the different relations existing between 
plants and their environment. How vegetable life 
originated, from what inorganic forms it was evolved, 
is a secret which science has not yet discovered; but 
since those dim first beginnings it has never been 
absent from the Earth, so far as we know, and has 
increased and multiplied, and passed through a thou- 
sand changes to higher and higher forms, till it has 
attained to the beautiful and bountiful and varied 
plant world which we know, covering with a green 
mantle most of the land surface of the globe and 
filling the shallower lakes and seas; while in its minuter 
forms it swarms in the soils and waters of the Earth, 
and its germs pervade the atmosphere. 
It is not everywhere even on our hospitable, habitable 
globe that conditions are suitable for plant growth. 
The reader will remember that the flat summit of Farle- 
ton Fell, where in fancy we still stand, was devoid to a 
great extent of vegetation; and that the sea-sands 
and mud-flats out to the westward presented a surface 
