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OBSERVATIONS FOR YOUNG BOTANISTS. 
XL — The Origin of Species. 
HE subject of this article has caused a great deal of 
discussion during the last forty years ; but after all. 
it is not a very abstruse matter, if we go straight 
to Nature and study her ways of doing things. 
Just as all human beings have undoubtedly descended from 
some common stock, but can be grouped into many races, so is 
it with plants. Thus we have a large number of “ species” of 
buttercups, and we should infer that they had all descended from 
some common ancestor ; but we cannot actually prove it, and 
the way we arrive at the belief is by an accumulation of prohabili- 
ties till it amounts to a conviction or certainty. This is called 
inductive^ evidence. As an example : it was formerly thought 
that the earth stood still while the sun went round it in twenty- 
four hours. Since, however, it is a much simpler thing for the 
earth to revolve on its axis, than the sun to travel 540,000,000 
miles in twenty-four hours, to say nothing of all the stars, which 
must revolve at far greater distances and rates, we believe the 
former, but it cannot be otherwise “ proved.” 
Now when comparatively few animals and plants were 
known, they seemed to be very distinct, and all were supposed 
to have been created just as they are. Explorations, however, 
soon brought to light hundreds of thousands, and species which 
seemed at first to be very distinct were found to be, so to say, 
linked together by intermediate forms, thus furnishing a gradu- 
ated series from one clearly defined species to another as equally 
clearly defined, when considered apart. Not only is this a very 
common feature in both living animals and plants, but it is 
equally so among extinct fossil animals, such as shells. The 
inference was that the members of these series of creatures of the 
same kind, or “ genus,” had somehow been “ evolved ” one from 
another. While, therefore, successive generations resembled 
their parents by heredity, yet coupled with the family likeness, 
there appeared to be a power to vary more or less from it. How 
was this “ Theory of Evolution ” to be proved } First, by induc- 
tive evidence. Thus it strikes one as much more probable that 
the innumerable instances of transitions have thus arisen, than 
that each slight variation had required a separate act of creation. 
Secondly, we verify or prove the fact of this power to vary 
by cultivation. When wild plants are grown in a garden, we 
find that the seedlings vary on growing up to the adult stage, 
and these variations increase with succeeding generations, so 
that from one original common wild form we can get any 
number of cultivated “ races,” as in carrots, parsnips, wheats. 
facts. 
A word derived from tlie Latin in and dnco, “ to lead in ” or accumulate 
