On the Origin of Species by Means of Natural Selection: Or The Preservation of Favoured Races in the Struggle for LifeHumphrey Milford, Oxford University Press, 1923 - 454 páginas |
Dentro del libro
Resultados 1-5 de 75
Página 9
... hand , we see domesticated animals and plants , though often weak and sickly , yet breeding quite freely under confinement ; and when , on the other hand , we see individuals , though taken young from a state of nature , perfectly tamed ...
... hand , we see domesticated animals and plants , though often weak and sickly , yet breeding quite freely under confinement ; and when , on the other hand , we see individuals , though taken young from a state of nature , perfectly tamed ...
Página 38
... hand , nurserymeu , from raising large stocks of the same plants , are generally far more successful than amateurs in getting new and valuable varieties . The keeping of a large number of individuals of a species in any country requires ...
... hand , nurserymeu , from raising large stocks of the same plants , are generally far more successful than amateurs in getting new and valuable varieties . The keeping of a large number of individuals of a species in any country requires ...
Página 39
... hand , cats , from their nocturnal rambling habits , cannot be matched , and , although so much valued by women and children , we hardly ever see a distinct breed kept up ; such breeds as we do sometimes see are almost always im- ported ...
... hand , cats , from their nocturnal rambling habits , cannot be matched , and , although so much valued by women and children , we hardly ever see a distinct breed kept up ; such breeds as we do sometimes see are almost always im- ported ...
Página 46
... hand , they are united by many intermediate links , and it is very doubtful whether these links are hybrids ; and there is , as it seems to me , an overwhelming amount of experimental evidence , showing that they descend from common ...
... hand , they are united by many intermediate links , and it is very doubtful whether these links are hybrids ; and there is , as it seems to me , an overwhelming amount of experimental evidence , showing that they descend from common ...
Página 51
... hand , if we look at each species as a special act of creation , there is no apparent reason why more varieties should occur in a group having many species , than in one having few . To test the truth of this anticipation I have ...
... hand , if we look at each species as a special act of creation , there is no apparent reason why more varieties should occur in a group having many species , than in one having few . To test the truth of this anticipation I have ...
Otras ediciones - Ver todas
Términos y frases comunes
accumulated adapted affinities allied species America amount analogous ancient appear Archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour common parent continuous crossed crustaceans degree difficulty distinct species divergence doubt embryo endemic Europe existing exterminated extinct extremely facts favourable fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing land larvæ less living male mammals manner Marsupials migration modification modified descendants natural selection naturalists nearly nest oceanic islands offspring organisation perfect pigeons pistil plants pollen present principle probably produced progenitor ranked reciprocal crosses remarked resemble rock-pigeon rudimentary organs seeds sexual selection Silurian slight South America sterility structure struggle successive suppose swimbladder tend theory tion trees variability variation vary whole widely