The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . Fig. 107. The Madder. Ruhia tinctortim. Fasciated stemswith an increased number of leaves in the whorls, foundin a madder field near Ouwerkerk and broken off at therhizome (1890). Where the fasciations are very broad this was to be ex-pected, as for instance in the case of Scdiiiu rcflcxuiucristatiiiu figured in the first volume (Figs. 34-35, ])p. 494 Tlic lucoiistancy of Fasciatcd Races, 182-183). Expanded combs of this kind are often seenat the top of inflorescences, especially in Veronica l
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . Fig. 107. The Madder. Ruhia tinctortim. Fasciated stemswith an increased number of leaves in the whorls, foundin a madder field near Ouwerkerk and broken off at therhizome (1890). Where the fasciations are very broad this was to be ex-pected, as for instance in the case of Scdiiiu rcflcxuiucristatiiiu figured in the first volume (Figs. 34-35, ])p. 494 Tlic lucoiistancy of Fasciatcd Races, 182-183). Expanded combs of this kind are often seenat the top of inflorescences, especially in Veronica longi-. Fig. io8. J^croiiica longifoJia. Inflorescence with tlie tipexpanded in the form of a comh. folia (Fig. 108), Ainarantus speciosus (Fig. 83, p. 399),Oeiinfliera Lamarckiana and 0. breiisfylis, etc. The Jii/irri/aiicc of jasciatiojis. 495 Tliese phenomena have l)een more closely investigatedby Nestler who regularly found inside the terminal budof a fasciated branch a line of fasciation instead of apoint, in other words a growing comb instead of a grow-ing ^ The leaves arising from this latter are pro-duced in ver} large numbers and in an abnormal arrange-ment, and in consequence of this, the disposition of theleaves on fasciated stems tends to be extremely irregular;but although this subject is obviously very important inits bea-hig on the whole question of phyllotaxy, it stillawaits a thorough investigation. In this respect it wouldbe particularly valuable t^o make a study of fasciations inconifers, for our knowledge of the normal structure oftlieir cone of vegetation is much mo
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