The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . wing, and it was not necessary to pay any furtherattention to the development of the character; this wasfully insured. Nevertheless I took care by means of further experiments to sat-isfy myself that there existsa fairly close relation be-tween a large number of 4-7-merous leaves on a plant anda high percentage of abnor-mal seedings produced by July 1893 I only savedthe 12 best plants raisedfrom the seed of the plantof 1892 with 60% abnormaloftspring. With the excep-tion of two plants th
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . wing, and it was not necessary to pay any furtherattention to the development of the character; this wasfully insured. Nevertheless I took care by means of further experiments to sat-isfy myself that there existsa fairly close relation be-tween a large number of 4-7-merous leaves on a plant anda high percentage of abnor-mal seedings produced by July 1893 I only savedthe 12 best plants raisedfrom the seed of the plantof 1892 with 60% abnormaloftspring. With the excep-tion of two plants they allbore not only 4-6-foliateleaves, Lmt even some 7-merous ones. The four best had 27, 30, 33 and 34 ofthis latter type. There were no leaves with more thanseven leaflets. The plant with 34 7-merous leaves also produced thehighest percentage of abnormal seedlings, as shown bvthe result of the sowing in the following spring. Of 209seedlings produced, 51 had a bimerous, and 61 a trimer-ous, primordial leaf, i. e., 55% of abnormalities. It wastherefore chosen as seed-parent (see p. 38). It should. Fig. 4- TrifoUum pratcnse quin-que folium. A, Seedling witha trifoliate primordial , C, Seedlings with singleand bimerous primordialleaves ; these two latter typeswere regarded in my race asatavistic. Trifoliiim Pratcnsc Qnuiqucfoliiun. 43 be remarked that in previous years seedlings with a com-pound primordial leaf had either been entirely absent orat any rate very rare.^ In the summer of 1894 I only bred offspring fromthe plant with 55% of abnormalities in its seedlings, andof these only the twenty best, with compound primordialleaf and the next leaf tetra-pentamerous. These onlydid I allow to flower and to bear seed. The result wasrecorded by means of the same characters in the followingspring. For eleven plants it was 70-90%, for five others91-967c, and for the two best 98-99% seedlings withcompound primary leaf. And the higher the number thegreater was the percentage of tri
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