The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . stinctly visible red flush can be seen on any bed of them in full flower. Sometimesoccasional plants or individualflowers are somewhat richer inpigment, so that it is at onceobvious that they are not purewhite. I have only made an in-complete series of experimentswith this plant because it doesnot lend itself easily to artificialfertilization and, as a rule, doesnot stand transplanting whilein flower. But the results ob-tained suffice to demonstratetheir essential correspondencewith those obta
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . stinctly visible red flush can be seen on any bed of them in full flower. Sometimesoccasional plants or individualflowers are somewhat richer inpigment, so that it is at onceobvious that they are not purewhite. I have only made an in-complete series of experimentswith this plant because it doesnot lend itself easily to artificialfertilization and, as a rule, doesnot stand transplanting whilein flower. But the results ob-tained suffice to demonstratetheir essential correspondencewith those obtained with Antirrhinum and Hcsperis. We can distinguish in this as in the other two casesbetween a pale race poor in stripes and a richly stripedone; moreover these two races possess the characters ofthe corresponding ones in the two species named. Butin Clarkia the broad stripes appear chiefly as sectors, as ^ There is also a variety, Carnea, which is constant so far as myexperience goes. See p. 119. It was referred to by Vilmorin and hy B. Verlot,Production et fixafion des varictcs, 1865, p. Fig. 25. Clarkia white flower of whichone petal and a half aredark red, while there aredark red stripes here andthere on the other twopetals. Clarkia PulchcUa. 145 for instance, wliolc or half petals; T shall therefore callsuch flowers and plants sectorial. In 1896 I had a bed of about 50 plants all of theflowers of which were whitish. The majority bore nored stripes, or only such fine ones and so rarely that theywere overlooked, which is always possible since the ])lantsproduce very many and rapidly fading flowers. Onlyone ])lant stood out amongst the rest; at the end of Julyit bore a flower with two red petals and at the beginningof August a petal the middle third of which was alsocolored red. Otherwise, the bed was practically whitethroughout the summer. Some of the seed of the whiteswas saved. From the seeds of a w^hite flowered specimen I ob-tained in 1897 a culture o
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