MORPHOLOGY, between members of the same class, between parts of the
same individual.
EMBRYOLOGY, laws of, explained by variations not supervening at an
early age, and being inherited at a corresponding age.
RUDIMENTARY ORGANS; their origin explained.
Summary.


CHAPTER 14. RECAPITULATION AND CONCLUSION.

Recapitulation of the difficulties on the theory of Natural Selection.
Recapitulation of the general and special circumstances in its favour.
Causes of the general belief in the immutability of species.
How far the theory of natural selection may be extended.
Effects of its adoption on the study of Natural history.
Concluding remarks.



ON THE ORIGIN OF SPECIES.



INTRODUCTION.

When on board H.M.S. 'Beagle,' as naturalist, I was much struck with
certain facts in the distribution of the inhabitants of South America,
and in the geological relations of the present to the past inhabitants
of that continent. These facts seemed to me to throw some light on the
origin of species--that mystery of mysteries, as it has been called by