Archive image from page 309 of The different forms of flowers The different forms of flowers on plants of the same species differentformsof00darw Year: 1897 294 DICECIOITS AND Chap. VII known to be dioecious. My son William found tlie two sexes growing in about equal numbers in the Isle of Wight, and sent me specimens, together with obser- vations on them. Each sex consists of two sub-forms. The two forms of the male differ in their pistils: in some plants it is quite small, without any distinct stigma; in others the pistil is much more developed, with the papillae on the stigmatic surfaces
Archive image from page 309 of The different forms of flowers The different forms of flowers on plants of the same species differentformsof00darw Year: 1897 294 DICECIOITS AND Chap. VII known to be dioecious. My son William found tlie two sexes growing in about equal numbers in the Isle of Wight, and sent me specimens, together with obser- vations on them. Each sex consists of two sub-forms. The two forms of the male differ in their pistils: in some plants it is quite small, without any distinct stigma; in others the pistil is much more developed, with the papillae on the stigmatic surfaces moderately large. The ovules in both kinds of males are in an aborted condition. On my mentioning this case to Pro- fessor Caspary, he examined several male plants in the botanic gardens at Konigsberg, where there were no females, and sent me the accompanying drawings. Fig. 13. Long-styled male. Short-styled male. RllAMNUS CATHARTICUS. (From Caspary.) In the English plants the petals are not so greatly reduced as represented in this drawing. My son ob- served that those males which had their pistils mode- rately well developed bore slighly larger flowers, and, what is very remarkable, their pollen-grains exceeded by a little in diameter those of the males with greatly reduced pistils. This fact is opposed to the belief that the present species was once heterostyled; for in this case it might have been expected that the shorter- styled plants would have had larger pollen-grains. In the female plants the stamens are in an ex- tremely rudimentary condition, much more so than
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