396 



ANOMALOUS EEPEODTJCTION, ETC. 



^HAP. XI 



mottled colour apparently affords clear evidence of the intimate com- 

 mingling of the two varieties. I have repeated these experiments on the 

 potato and on the hyacinth on a large scale, but with no success ; but Dr. 

 Hildebrand informs me in a letter dated Jan. 2nd, 1868, that he has 

 recently succeeded with the potato. He removed all the eyes from a 

 white, smooth-skinned potato, and all from a red scaly potato, and inserted 

 them reciprocally into each other. From these eyes he raised only two 

 plants ; and of the tubers formed by them two were red and scaly at one 

 end, and white and smooth-skinned at the other end; the middle part 

 being white with red streaks. Hence the possibility of the production of a 

 graft-hybrid may be looked at as established. 



The most reliable instance known to me (with the exception of the 

 case just given) of the formation of a graft-hybrid is one, recorded by 

 Mr. Poynter, 115 who assures me, in a letter of the entire accuracy of the 

 statement. JRosa Devoniensis had been budded some years previously 

 on a white Banksian rose ; and from the much enlarged point of junc- 

 tion, whence the Devoniensis and Banksian still continued to grow a 

 third branch issued, which was neither pure Banksian nor pure Devoni- 

 ensis, but partook of the character of both ; the flowers resembled, but 

 were superior in character to those of the variety called Lamarque (one 

 of the Noisettes), while the shoots were similar in their manner of growth 

 to those of the Banksian rose, with the exception that the longer and 

 more robust shoots were furnished with prickles. This rose was exhi- 

 bited before the Floral Committee of the Horticultural Society of London. 

 Dr. Lindley examined it, and concluded that it had certainly been pro- 

 duced by the mingling of B. Banhsice with some rose like B. Devoniensis, 

 "for while it was very greatly increased in vigour and in the size of 

 all the parts, the leaves were half-way between a Banksian and Tea- 

 scented rose." It appears that rose-growers were aware that the Banksian 

 rose sometimes affects other roses. Had it not been for this latter state- 

 ment, it might have been suspected that this new variety was simply due 

 to bud-variation, and that it had occurred by a mere accident at the point 

 of junction between the two old kinds. 



To sum up the foregoing facts : the statement that Cytisus 

 adami originated as a graft-hybrid is so precise that it can hardly 

 be rejected, and the facts given above show that this is 

 certainly possible. The peculiar, monstrous condition of the 

 ovules, and the apparently sound condition of the pollen, 

 favour the belief that it is not an ordinary or seminal hybrid. 

 On the other hand, the fact that the same two species, viz. 

 0. laburnum and purpureus, have spontaneously produced 

 hybrids by seed, is a strong argument in support of the 

 belief that C. adami originated in a similar manner. With 

 respect to the extraordinary tendency which this tree exhibits 

 115 ■ Gard. Chron.,' 1860, p. 672, with a woodcut. 



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fl 1 



%Spliical 



