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HAROLD’S DISCUSSIONS. 
by Explosion ” to the periods in the life history of 
the globe that are especially rich in new species. It 
seems to these scientists that an old species explodes, 
as it were, some of the fragments disappearing and 
others becoming new species. They think that this 
would account for the sudden appearance of others, 
also for the interval of rest. It is assumed that 
groups of varieties, like individuals, have a time of 
birth, a period for maturing, followed by decline and 
death. These suggestions are attracting some atten¬ 
tion, but to what extent they can be made helpful re¬ 
mains to be proved. 
REVEALS AN INTELLIGENT PLAN. 
As far as we can see, life began with the unicel¬ 
lular form of being, the lowest that man has been 
able to discover. Environment and selection have 
done much to change its forms; still, there are many 
facts about life unexplained. From time to time new 
features appear as suddenly as the beginning of life, 
and each seems to be a step in the direction of a 
higher goal, as if the whole were planned and directed 
by a supreme intelligence. 
The evolution of man’s inventions affords at least 
a suggestive parallel to the evolution of life. Take, 
for instance, our modern self-binder. The beginning 
was made when man used the sharp-edged stone for 
cutting. This led to the polished edge, then to a 
bronze knife, and finally the sickle and cradle. Here 
there was a long halt. Then suddenly the reaper 
loomed up, making use of all that had preceded it. 
