The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . Fig. 105. Ranuuciihis biilbosus. A fasciated stem whichhas grown up from a broadened rosette of radical terminal flower is also broadened and split. Hilver-sum, 1894. of fasciations, they are scarcely inferior to the best fas-ciated specimens of the race. The character in questionis only latent in them, or rather only temporarily invisible;perhaps simply not developed by reason of the absenceof some necessarv external factors. The atavists do not, so to speak, depart from therace, a
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . Fig. 105. Ranuuciihis biilbosus. A fasciated stem whichhas grown up from a broadened rosette of radical terminal flower is also broadened and split. Hilver-sum, 1894. of fasciations, they are scarcely inferior to the best fas-ciated specimens of the race. The character in questionis only latent in them, or rather only temporarily invisible;perhaps simply not developed by reason of the absenceof some necessarv external factors. The atavists do not, so to speak, depart from therace, as do those of Oenothera scintillans; the race con- The Inheritance of Fasciations. 491 stitutes a uniforni group of individuals and only differsfrom constant races or true varieties by the extraordi-narily high degree of variability of its distinguishingcharacter. This degree of variability relates not only to thedegree of expansion of the axis, but also to the mannerin which the anomaly is manifested. First we have to. Fig. ]o6. Viola tricolor maxima, the garden pansy. Aforked flower stalk arising from the axil of a doubleleaf {a,a) ; ., the outer stipules; s , the inner un-split stipules of this leaf. The continuation of the mainaxis has been bent down laterally, {b). distinguish between the split branches and the fasciatedbranches scnsn sfricfo. Split ears of the rye are some-times found in the fields (Fig. 104) and then preservedby the country folk. The axis of these ears may bedivided once or oftener, the parts above the divisionbeing perfectly normal themselves. Or again the haulm 492 The Iiiconstaucy of Fasciafcd Races. below the ear may be split and produce two ordinaryears side by side. Amongst other plants also forkingsof this kind are by no means rare, but as a rule theyoccur associated with typical fasciations. The latter are of the same breadth from below, thatis to say in the strict sense ribbon-shaped, or they beginwith a cylindrical form below, and gradual
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