Contributions to the theory of natural selection. A series of essays ... By Alfred Russel Wallace ...

CONTENTS.
I.-Onr the Law which has regulated the introduction of New
Species.
Geographical distribution dependent on Geologic Changes -A Law
deduced from well-known Geographical and Geological facts-The
form of a true system of Classification determined by this Law-Geographical Distribution of Organisms-Geological Distribution of the
forms of Life-High Organization of very ancient Animals consistent
with this Law-Objections to Forbes' Theory of Polarity-Rudimentary Organs-Conclusion...Pp. 1-25
II.-On the Tendency of Varieties to depart inclefinitely from the
Original Type.
Instability of Varieties supposed to prove the permanent distinctness of
Species-The Struggle for Existence —The Law of Population of
Species-The Abundance or Rarity of a Species dependent upon its
more or less perfect Adaptation to the Conditions of ExistenceUseful Variations will tend to Increase, useless or hurtful Variations
to Diminish-Superior Varieties will ultimately extirpate the Original Species —The Partial Reversion of Domesticated Varieties
explained - Lamarck's Hypothesis very different from that now
advanced-Conclusion.. Pp. 26-44
III.-Minmicry, and other Protective Resemblances among
Animals.
Test of true and false Theories-Importance of the Principle of Utility
-Popular Theories of Colour in Animals-Importance of Concealment as influencing Colour-Special modifications of Colour-Theory
of Protective Colouring-Objection that Colour as being dangerous
should not exist in Nature-Mimicry-Mimicry among Lepidoptera
-Lepidoptera mimicking other Insects-Mimicry among BeetlesBeetles mimicking other Insects-Insects mimicking Species of other
Orders-Cases of Mimicry among the Vertebrata —Mimicry among
Snakes-Mimicry among Birds-Mimicry among Mammals-Objec