This etext was prepared by Sue Asscher asschers@dingoblue.net.au from the etext prepared by Robert J. Robbins, PhD of the ESP Project http://www.esp.org/rjr THE VARIATION OF ANIMALS AND PLANTS UNDER DOMESTICATION BY CHARLES DARWIN, M.A., F.R.S., ETC. IN TWO VOLUMES VOLUME II. CONTENTS. CHAPTER 2.XIII.--INHERITANCE continued--REVERSION OR ATAVISM. DIFFERENT FORMS OF REVERSION--IN PURE OR UNCROSSED BREEDS, AS IN PIGEONS, FOWLS, HORNLESS CATTLE AND SHEEP, IN CULTIVATED PLANTS--REVERSION IN FERAL ANIMALS AND PLANTS--REVERSION IN CROSSED VARIETIES AND SPECIES--REVERSION THROUGH BUD-PROPAGATION, AND BY SEGMENTS IN THE SAME FLOWER OR FRUIT--IN DIFFERENT PARTS OF THE BODY IN THE SAME ANIMAL--THE ACT OF CROSSING A DIRECT CAUSE OF REVERSION, VARIOUS CASES OF, WITH INSTINCTS--OTHER PROXIMATE CAUSES OF REVERSION--LATENT CHARACTERS--SECONDARY SEXUAL CHARACTERS--UNEQUAL DEVELOPMENT OF THE TWO SIDES OF THE BODY--APPEARANCE WITH ADVANCING AGE OF CHARACTERS DERIVED FROM A CROSS--THE GERM, WITH ALL ITS LATENT CHARACTERS, A WONDERFUL OBJECT--MONSTROSITIES--PELORIC FLOWERS DUE IN SOME CASES TO REVERSION. CHAPTER 2.XIV.--INHERITANCE continued.--FIXEDNESS OF CHARACTER--PREPOTENCY-- SEXUAL LIMITATION--CORRESPONDENCE OF AGE. FIXEDNESS OF CHARACTER APPARENTLY NOT DUE TO ANTIQUITY OF INHERITANCE-- PREPOTENCY OF TRANSMISSION IN INDIVIDUALS OF THE SAME FAMILY, IN CROSSED BREEDS AND SPECIES; OFTEN STRONGER IN ONE SEX THAN THE OTHER; SOMETIMES DUE TO THE SAME CHARACTER BEING PRESENT AND VISIBLE IN ONE BREED AND LATENT IN THE OTHER--INHERITANCE AS LIMITED BY SEX--NEWLY-ACQUIRED CHARACTERS IN OUR DOMESTICATED ANIMALS OFTEN TRANSMITTED BY ONE SEX ALONE, SOMETIMES LOST BY ONE SEX ALONE--INHERITANCE AT CORRESPONDING PERIODS OF LIFE--THE IMPORTANCE OF THE PRINCIPLE WITH RESPECT TO EMBRYOLOGY; AS EXHIBITED IN DOMESTICATED ANIMALS: AS EXHIBITED IN THE APPEARANCE AND DISAPPEARANCE OF INHERITED DISEASES; SOMETIMES SUPERVENING EARLIER IN THE CHILD THAN IN THE PARENT--SUMMARY OF THE THREE PRECEDING CHAPTERS. CHAPTER 2.XV.--ON CROSSING. FREE INTERCROSSING OBLITERATES THE DIFFERENCES BETWEEN ALLIED BREEDS--WHEN THE NUMBERS OF TWO COMMINGLING BREEDS ARE UNEQUAL, ONE ABSORBS THE OTHER--THE RATE OF ABSORPTION DETERMINED BY PREPOTENCY OF TRANSMISSION, BY THE CONDITIONS OF LIFE, AND BY NATURAL SELECTION--ALL ORGANIC BEINGS OCCASIONALLY INTERCROSS; APPARENT EXCEPTIONS--ON CERTAIN CHARACTERS INCAPABLE OF FUSION; CHIEFLY OR EXCLUSIVELY THOSE WHICH HAVE SUDDENLY APPEARED IN THE INDIVIDUAL--ON THE MODIFICATION OF OLD RACES, AND THE FORMATION OF NEW RACES BY CROSSING--SOME CROSSED RACES HAVE BRED TRUE FROM THEIR FIRST PRODUCTION--ON THE CROSSING OF DISTINCT SPECIES IN RELATION TO THE FORMATION OF DOMESTIC RACES. CHAPTER 2.XVI.--CAUSES WHICH INTERFERE WITH THE FREE CROSSING OF VARIETIES-- INFLUENCE OF DOMESTICATION ON FERTILITY.