622 J'alidify of flic Doctrine of Muiation. 



stock in hybrids of HcHanfhcininn.^ Hybrid peas may 

 be partly green and partly yellow- and similar segrega- 

 tions have been found by Correns and Webber on grains 

 of hybrid maize. 



Bnt the best known instance of a vegetative segrega- 

 tion is furnished l)y Cyfisiis Adaiiii {C. Laburnuui X 

 piirpurcns), wliich any one can observe in his garden 

 or in parks. The hybrid is a1)solutely sterile, and all 

 the specimens of it are grown from cuttings from one 

 single individual, ^^dlether the extraordinary tendency 

 to segregate is peculiar to this hybrid as such, or to this 

 particular individual, we cannot knov/.'"^ The fact is, 

 that this hybrid is intermediate between its two parents 

 and besides this produces from time to time buds, of 

 which some l)ecome strong branches of C. Lahuvnuin 

 with its large leaves and long racemes (Fig. 139L), 

 whilst from others the delicate, slender and bushy 

 branches of C. piirpiircus arise, bearing their fruits and 

 flowers either singly or in small groups (Fig. MOP"). 



The current view is that C. Adami is a graft hybrid. "* 

 There is, however, neither an historical nor a physiolog- 

 ical justification for this view.'" The original raiser of 

 the plant, the Parisian gardener Adam, seems himself 

 to have thought that this form which he put on the 



^FocKE. Die PHanacnmischlin^c, p. 473. wliere further instances 

 will be found. See also Br.mjn. Verji'inguiiii, p. 336; Darwin. Ani- 

 mals and Plants Under Doinesfieafion. etc. Similar facts are afforded 

 bv Hieraeiuin. Oxalis, Chamaedorea etc.: see F. Hilderrand, Jen. 

 Zeifsehriff. Vol. XXITT. 1889. Plate XXV. 



" F. Weldon, Bionictrika, T, 2. 1902. 



' See the remarks relating to Datura on the foregoing pages. 



* Infraeellnlare Pangenesis (Ger. ed.). p. 206. 



'■ T have given an historical account of Cytisus Adami. in Dutch, 

 in the Album der Natuur, 1894, Part 7. under the title Adam's Gouden 

 Regen. The original source of the historical data is found in Annales 

 de la Societe hortieole de Paris, Vol. VI T, 1830. 



