The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . Fig. 148. Pedigree of Ocnotlicra Lamarckiana, exhibitingthe yearly origin of new species in my experimentalgarden in the years 1889-1899. g, O. gigas; a, O. albida;It, O. lata; 11, O. nanella; r, O. nihrincrvis; o, O. oblonga;s, O. sciufillans. The numbers preceding the letters arethose in which the species in question arose. The num-bers on the main stem show the extent of the yearly cul-tures. TJic Periodicity of Proyrcssiic Mutations. 655 XylonrCtuxum. Kn^iih Fig. 149. Schematic pedigree of
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . Fig. 148. Pedigree of Ocnotlicra Lamarckiana, exhibitingthe yearly origin of new species in my experimentalgarden in the years 1889-1899. g, O. gigas; a, O. albida;It, O. lata; 11, O. nanella; r, O. nihrincrvis; o, O. oblonga;s, O. sciufillans. The numbers preceding the letters arethose in which the species in question arose. The num-bers on the main stem show the extent of the yearly cul-tures. TJic Periodicity of Proyrcssiic Mutations. 655 XylonrCtuxum. Kn^iih Fig. 149. Schematic pedigree of progressive formation ofspecies; based on Ocnotlicra LuDiarihiana. The uppergroup is a reduced form of Fig. 148. and contains thesame new species. Onagra is the sub-genus to whichOcnottiera Lainarcluana belongs. Euocnothcra, Ktiriffi*!and Xyloptciiniui are other sulvgenera of Orih> two small groups of lateral branches which ha\i-been intercalated are intended to rcjirosent the sexrralintermediate periods of mutation. Tlie figure can becontinued downwards in a similar manner. 656 Geological Periods of Mutation. If now we follow this stem downwards, we must ob-viously sooner or later arrive at another mutation period,and of course one of which, although direct observationis no longer possible, so many products remain, that wemay conclude with a high degree of probability its simi-larity with the period observed by me. I am referringto the differentiation of the sub-genus Onagra, and of itsnumerous species such as 0. biennis L., O. mur
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