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life in the world (whenever that may have been) there has been 
one continuously connected stream of life ; no universal destruction, 
no gap or blank; with the progress of time living forms, both 
animal and vegetable have multiplied without cessation, both in 
number and variety. How, again, did the varzety, the new forms, 
appear ? Were they each individually fashioned, perfect in form 
and kind, or were several forms developed out of one? The 
advocates of development adhere to the latter view: e.y. that all 
kinds of elephant have descended from one origimal form, not 
exactly like any of them; so with all forms of rhinoceros, hippo- 
potamus, tapir, &c.—that all these various forms may probably — 
have had one common ancestor ; that all butterflies have descended 
from an ancestor probably common to them and tu moths,—that 
indeed all insects have had a common origix ; and so with flowers. 
You will ask upon what grounds such a view has been adopted. 
I will sum them up briefly. 
1.—No two animals or plants of the same kind are exactly alike. 
There is an innate and unexplained tendency in each to vary from 
its parent in some particulars more or less slight, in spite of its 
general resemblance. ‘This requires no proof whatever; you never 
find two leaves on the same tree, one the exact duplicate of the 
other. 
2.—Such variations can be, and very often are, transmitted to 
offspring—the latter tends to inherit the peculiarities of its parent. 
These peculiarities may be either an advantage or a disadvantage, 
it depends on circumstances around. 
8.—More animals and plants are produced than could possibly 
find room on the earth if they lived what one might call their 
natural term of life. Therefore many disappear in a more or less 
abrupt manner. But which of them ? 
4.—Surely those whose peculiarities were a disadvantage to them. 
If a variation in certain individuals better fitted them either to 
obtain food, or to escape from enemies, these individuals would be 
preserved while the less favoured ones perished. Those that are 
best adapted to surrounding physical circumstances—-they will be 
the survivors. The carnivore that can catch the most food when 
itis scarce; the deer that by its longer legs or stronger muscles can 
best escape the beast of prey; the sheep that has the thickest 
fleece when climate changes for the worse, &c. This has been 
happily styled ‘‘ the survival of the fittest.” 
Just as man selects those animals and plants best suited to his 
wants on account of some accidental variation, and breeds from 
them, thereby artificially producing new varieties, if not species, so 
there is a ‘‘natural selection” going on around us; some hold 
merely through the working of a blind law, others, through a con- 
