The Origin of Species by Means of Natural Selection, Or, The Preservation of Favored Races in the Struggle for Life, 1-2권D. Appleton, 1917 |
도서 본문에서
85개의 결과 중 1 - 3개
72 페이지
... varieties but groups of forms , unequally related to each other , and clustered round certain forms - that is , round their parent - species . Undoubtedly there is one most important point of dif- ference between varieties and species ...
... varieties but groups of forms , unequally related to each other , and clustered round certain forms - that is , round their parent - species . Undoubtedly there is one most important point of dif- ference between varieties and species ...
212 페이지
... varieties in a state of nature . I have met with striking instances of the rule in the case of varie- ties intermediate between well - marked varieties in the genus Balanus . And it would appear from information given me by Mr. Watson ...
... varieties in a state of nature . I have met with striking instances of the rule in the case of varie- ties intermediate between well - marked varieties in the genus Balanus . And it would appear from information given me by Mr. Watson ...
39 페이지
... varieties , when used either as the father or mother , and crossed with the Nicotiana glutinosa , always yielded hybrids not so sterile as those which were produced from the four other varieties when crossed with N. glutinosa . Hence ...
... varieties , when used either as the father or mother , and crossed with the Nicotiana glutinosa , always yielded hybrids not so sterile as those which were produced from the four other varieties when crossed with N. glutinosa . Hence ...
기타 출판본 - 모두 보기
자주 나오는 단어 및 구문
adapted affinity allied species ancient animals appear Archipelago beak become believe belonging birds breeds Cambrian cause characters climate closely allied colour common continent crossed crustaceans degree developed difficulty distinct species domestic doubt eggs embryo Europe existing extinct extremely facts favourable fertilised fertility fish flowers formation formerly forms fossil Fritz Müller Gärtner genera genus geological geological period Glacial period gradations groups of species habits Hence hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing intermediate land larvæ less living male mammals manner Marsupials migration modified descendants natural selection naturalists nearly occur oceanic islands offspring organisation parent peculiar perfect pigeon pistil plants pollen present probably produced progenitor quadrupeds ranked reciprocal crosses remarked resemblance seeds Silurian slight South America stage stamens sterility structure successive suppose theory tion variability variations varieties vary whilst whole widely different wings