I do not, however, believe that if all known plants were tried in the same manner, half would be found to be sterile within the specified limits ; for many flowers were selected for experiment which presented some remarkable structure ; and such flowers... The American Journal of Science and Arts - Seite 1321877Vollansicht - Über dieses Buch
| Charles Darwin - 1876 - 504 Seiten
...the stigma in order to ensure full fertility, there is at least a good chance of cross-fertilisation. I do not, however, believe that if all known plants...structure; and such flowers often require insect-aid. Thus out of the forty-nine genera in the first list, about thirty-two have flowers which are asymmetrical... | |
| Charles Darwin - 1877 - 706 Seiten
...the stigma in order to ensure full fertility, there is at least a good chance of cross-fertilisation. I do not, however, believe that if all known plants...structure; and such flowers often require insect-aid. Thus out of the forty-nine genera in the first list, about thirty-two have flowers which are asymmetrical... | |
| James Samuelson, Henry Lawson, William Sweetland Dallas - 1879 - 496 Seiten
...plants more or less self-fertile, and the other self-sterile without insect aid ; but he a'lds : — " I do not, however, believe that if all known plants...found to be sterile within the specified limits." f 2. Very few plants are known to be physiologically selfsterile when the pollen of a flower is placed... | |
| George Henslow - 1888 - 432 Seiten
...Pert., etc. , pp. 357 and 365), one of self-sterile, the other of self-fertile plants, and adds, " I do not, however, believe that if all known plants...remarkable structure ; and such flowers often require insect aid " (Ie, p. 270). The proportion of self-sterile plants is, in fact, extremely small. Miiller... | |
| George Henslow - 1888 - 380 Seiten
...Self Fert., etc., pp. 357 and 365), one of self-sterile, the other of self-fertile plants, and adds, " I do not, however, believe that if all known plants were tried in the same manner, half wonld be found to be sterile within the specified limits; for many flowers were selected for experiment... | |
| Asa Gray - 1889 - 416 Seiten
...striking one ; for whenever pollen has to be carried from the anthers to the stigma in order to insure full fertility, there is at least a good chance of...and Red Clovers) have a place in the first list ; T. arvense and T. procumbens in the second. Darwin refers to Mr. Miner's statement that " in the United... | |
| Asa Gray - 1889 - 426 Seiten
...striking one ; for whenever pollen has to be carried from the anthers to the stigma in order to insure full fertility, there is at least a good chance of...Trifolium repens and T. pratense (the common White and Eed Clovers) have a place in the first list ; T. arvense and T, procumbens in the second. Darwin refers... | |
| Charles Darwin - 1889 - 504 Seiten
...the stigma in order to ensure full fertility, there is at least a good chance of cross-fertilisation. I do not, however, believe that if all known plants were tried in the sanie manner, half would be found to be sterile within the specified limits ; for many flowers were... | |
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