LIFE: STERILITY FROM VARIOUS CAUSES.
ON THE GOOD DERIVED FROM SLIGHT CHANGES IN THE CONDITIONS OF LIFE--STERILITY
FROM CHANGED CONDITIONS, IN ANIMALS, IN THEIR NATIVE COUNTRY AND IN
MENAGERIES--MAMMALS, BIRDS, AND INSECTs--LOSS OF SECONDARY SEXUAL CHARACTERS
AND OF INSTINCTS--CAUSES OF STERILITY--STERILITY OF DOMESTICATED ANIMALS FROM
CHANGED CONDITIONS--SEXUAL INCOMPATIBILITY OF INDIVIDUAL ANIMALS--STERILITY OF
PLANTS FROM CHANGED CONDITIONS OF LIFE--CONTABESCENCE OF THE ANTHERS--
MONSTROSITIES AS A CAUSE OF STERILITY--DOUBLE FLOWERS--SEEDLESS FRUIT--
STERILITY FROM THE EXCESSIVE DEVELOPMENT OF THE ORGANS OF VEGETATION--FROM
LONG-CONTINUED PROPAGATION BY BUDS--INCIPIENT STERILITY THE PRIMARY CAUSE OF
DOUBLE FLOWERS AND SEEDLESS FRUIT.