 | 1860 - 966 pages
...never flying."* Then in tLe s;une page the author adds that certain considerations have mude him " believe that the wingless condition of so many Madeira...is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of 4ii-Cf4<ive generations each individual... | |
 | Charles Darwin - 1861 - 470 pages
...have habits of life almost necessitating frequent flight ; — these several considerations have made me believe that the wingless condition of so many...is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of successive generations each individual beetle... | |
 | Charles Darwin - 1864 - 472 pages
...have habits of life almost necessitating frequent flight ; — these several considerations have made me believe that the wingless condition of so many...is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of successive generations each individual beetle... | |
 | 1879 - 978 pages
...Madeira. How may the absence of wings in the Madeiran beetles be accounted fo^- ? Let Mr. Darwin reply : " Several considerations make me believe that the wingless...is mainly due to the action of natural selection, combined probably with disuse. For during many successive generations each individual beetle •which... | |
 | Charles Darwin - 1873 - 492 pages
...numerous, which absolutely require the use of their wings, are here almost entirely absent;—these several considerations make me believe that the wingless...is mainly due to the action of natural selection, combined probably with disuse. For • during many successive generations each individual beetle which... | |
 | Charles Elam - 1876 - 186 pages
...Mivart, in his Lessons from Nature, p. 300. 2 Origin of Species, p. 136. NATURAL SELECTION. 127 less condition of so many Madeira beetles is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of successive generations each individual beetle... | |
 | John Holmes Agnew, Walter Hilliard Bidwell, Henry T. Steele - 1877 - 812 pages
...never flying." * Then in the same page the author adds that certain considerations have made him " believe that the wingless condition of so many Madeira...is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of successive generations each individual beetle... | |
 | 1877 - 1212 pages
...the same page the author adds that certain considerations have made him " believe that the wiiigless condition of so many Madeira beetles is mainly due to the action of natural selection, but combined probably with disuse. For during thousands of successive generations each individual beetle... | |
 | 1879 - 794 pages
...Madeira. How may the absence of wings in the Madeiran beetles be accounted for ? Let Mr. Darwin reply : " Several considerations make me believe that the wingless...is mainly due to the action of natural selection, combined probably with disuse. For during many successive generations each individual beetle which... | |
 | Charles Darwin - 1882 - 492 pages
...excessively numerous, which absolutely require the use of their wings, are here almost entirely absent; — these several considerations make me believe that...is mainly due to the action of natural selection, combined probably with disuse. For "luring many successive generations each individual beetle which... | |
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... the wingless condition of so many Madeira beetles is mainly due to the action of natural selection, combined probably with disuse. For during many successive generations each individual beetle which flew least, either from its wings having been ever... 
