The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . re in thesusceptible period of their development during fineweather wnll produce more petals, quite independentlyof the order of the branch which bears them. This conclusion is supported by another set of obser-vations. In September 1892 the flowers, on the wliole,produced more petals than they did in August of tliesame vear. Or. to be more accurate, the number was sfreater Raniuiculiis Buibusiis Sciiiiplciiiis. 259 on those plants which opened their first flower in Se])-teniber, than on those
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . re in thesusceptible period of their development during fineweather wnll produce more petals, quite independentlyof the order of the branch which bears them. This conclusion is supported by another set of obser-vations. In September 1892 the flowers, on the wliole,produced more petals than they did in August of tliesame vear. Or. to be more accurate, the number was sfreater Raniuiculiis Buibusiis Sciiiiplciiiis. 259 on those plants which opened their first flower in Se])-teniber, than on those which had already begun to flowerin July and August. The number of individuals of theformer group was 77; they produced 1134 flowers du-ring the period ending with the beginning of November,•when I stopped recording. In the other grou]) there were295 plants which flowered, and they produced 4425 flow-ers. The distribution was as follows:^ Petals: S 6 7 8 9 10 11 12 13 14 15 16-31 Oldest plants. 409 532 638 690 764 599 414 212 80 29 18 20 September plants: 40 52 126 165 204 215 177 104 35 8 4 0. Fig. 53. Raiiiuiculiis bulbosus semiplcnus. A, curve of theplants Howering in August; S, curve of those floweringin September. The ligures at the base refer to the num-ber of petals per flower. These figures are exhibited graphically in Fig. ^Z;they have been reduced for convenience of comparisonso that the numbers in the two groups are about the apex of the curve of the early flowering plants isover the 9; it is the same curve which has already beengiven in Fig. 51 on page 249 for the year 1(S92. Theother curve has its apex over the 10, and also remainsabove the other curve in the right half of its course. The cause of this difference can only lie in the re-tarded germination. Fither the seeds which germinatelater are intrinsically more productive of pleiopetalous ^ See above, p. 2? yi?n Fig. :;? ^892). 260 Non-Isolablc Races. flowers^ (like the small, late-germinating seeds
Size: 2866px × 872px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisherchicagoopencourtpu
