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From these I had 119 flowering plants, out of which 106 were peloric and 13 one-spurred. The great majority, some 90%, were thus shown to be true to their new type. Whether the 10% reverting ones were truly atavists, or whether they were only vicinists, caused by stray pollen grains from another culture, cannot of course be decided with sufficient certitude.
But, on the contrary, the atavists, which are here the individuals with the stature and the characteristics of the lamarckiana, have become lamarckianas in their hereditary qualities, too. If their seed is saved and sown, their progeny does not contain any scintillans, or at least no more than might arise by ordinary mutations.
Besides these tests, others were performed, based only on the visible characters of the seedlings. The result was that this characteristic was almost useless as a criterion. The atavists gave, in the main, nearly the same hereditary percentages as the tricotyls and syncotyls, and their extremes were in each case far better constituted than the average of the chosen type.
One is the visible quality of the individuals and the other is the direct observation of the degree in which the attribute is transmitted. These are by no means parallel, and seem in some sense to be nearly independent of each other. The fact that the worst atavists may have the highest percentage of varietal units seems to leave no room for another explanation.
I have tried many other species, but always with the same result. Such atavists only arise by cultivation in the proximity of allied varieties, never in isolation. They are not real atavists, but only vicinists. In order to show this yet more clearly, I made another experiment with the white selfheal.
Hence, for selection purposes, the atavists must be considered to be in no way inferior to the typical specimens. If it had been possible to apply this principle to twisted and fasciated plants, and perhaps even to other monstrosities, I think that it will readily be granted that the chance of bringing even these races up to a percentage of 90% would have been large enough.
This constancy was proved by the experiments of Solms-Laubach, which I have repeated in my own garden during several years with seed received from him. No atavists or deviating specimens have been found among many hundreds of flowering plants.
One may even select the atavists, pollinate them purely and repeat this in a succeeding generation without any chance of changing the result. On an average the atavists may give lower hereditary figures, but the difference will be only slight. Such tricotylous double races offer highly interesting material for inquiries into questions of heredity, as they have such a wide range of variability.
Now the question arises, whether this mark is the best upon which to found selection. This seems to be quite doubtful. In the experiments on the heredity of the atavists, we have seen that they are, at least often, in no manner inferior to even the best inheritors of the race.
I took for my experiment the rough hawksbeard. In the summer of 1895 I isolated some atavists of the fifth generation of my race, which, by ordinary selection, gave in the average from 20-40% of fasciated stems. My isolated atavists bore abundant fruit, and from these I had the next year a set of some 350 plants, out of which about 20% had broadened and linear rosettes.
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