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Show 396 ANOMALOUS REl'RODUCTION, ETC. CHAP. XT. the union of the bisected buds ; and as tnhcrs arc produ~cd 1t)Y th ct1c~l'a rrr ment of subterranean branches an·s m· g r·r om the ma.m t ' s emt , 1mr moht tled colom apparently affords c1 c ar cvi' d en co of the m.· 1mat sc onc otmho-minrrling of the two varieti es. I have repeated these cxpcnmcn pot~o and on the hyacinth on a large s~a1e, butf \~~~ ~o~·~:~~~~c;~f a gmft- 'rhe most reliable instance known ° me 0 · . hyhn·d · c1 d ,_ M . Poynter m who assures me,, m a letter of IS one rccor c vY r. ' . · d l Jd d . ' f he statement ltosa Devon ~ens~s ha been met c the entire .a ccu. rac. y o1 t on a wln.t c 'n an1 { Sm. n r.o .", C '. nnd from the much some ycm s pr vwus Y · . · and Banksian still con-enlarged point of j~~J~c~o~, wh~n~~.,:~~ ~:~:~~e:~: neithe~ pure Banksian tinned to grow, .a ~ll' b ~·ancto~l~ of ' the character of both ; the flowers nor pure DevomcnsJS, u P~1 . t . t those of the variety called resembled but were snpen or m charac er o . . . . ' 1 N . . tt ) while the shoots were similar m thmr L a.murque (one of t 1e mse es ' · . · tl t l f tll to tl1ose Of the Banksian rose, with the excoptwn m t le manner o grow · · 1 · 1 1 'Il · longer an d more rob ust sl 1 00 ts were fmnished w1t 1 p.n CJ{ es. S 11·s tr osef was exhibited before the Floral Committee of the Horti cu~tural oc~c ! o L d D I indley examined it, and concluded that 1t had cer.tamly 1_ on on.od r.d ~,, the mi'ngling of R JJanlcwiw with some rose like R. vecn pr uce vY · . . . . d . ]) evouw. 11 st.s , "for wl1J'le l·t was very greatly mcreased m vBJg onuJ·r ·a n md the s1· zc o f a 11 tl 1e part s, the le•a ves were half-way between a a "stlm n anh t d . " It appears that rose-growers were aware 1at t o Tea-seen e rose. d 't t been for this Banksian rose sometim es affects other roses. Ila 1 .no . latter statement, it might have been suspected that tlus new van ct~ was simply due to bud-variation, and that it l1ad ?ccurred by a mere acCident at the point of junction between the two old kmds. T o sum up tlle ~oreoO 'oincbr facts: the stat• ement t• hat Cyti.s1us ad amz· on·g m· at e d as a gr·af't hybrid is so preCise that 1t can haru 1y ~ - b e reJ·e C t e d an d, a•s we have J. ust . seen ' some analogous facts render the 'statement to a certain extent probaule. 'fhe peen-liar monstrous condition of the ovules, and the apparently sound cm:dition of the pollen, favour the belief that it i not an· onlinary or seminal hyurid. On the other hand, the far.t that the same two species, viz. C. laburnum and purpureus, have ~pontancously produced hybrids by seed, is a str~ng ar?u~ ent m snpport. of the belief that 0. adami originated m a Similar ~anner. V~J.th 1:espect to the extraordinary tendency which tlus tree exlnbtts to complete or partial reversion, we have seen that undoubted seminal hybrids and mongrels are similarly liable. On the wl:ol~, I am inclined to put trust in M. Adam's statement; and If It should ever be proved. true, the same view would. probably have m • Gn.rd. Chron.,' 1860, p. G72, with a wootlcut. CHAP. XI. ACTION OF TilE MALE ELEll-fENT. 397 to Le extended to tlte Bizzarria and Trifacial oranges and to the apples auove deseril>ed; Lut more evidence is re qui~ite Lefore tlte possiuility of the production of graft-hyl>rids can be fully admitted. Although it is at present impossil>le to arrive at any 'certain conclusion with respect to the origin of these remarli: al>le trees, the various facts above given appear to me to deserve attention under several points of view, more especially as showing that the power of reversion is inherent in Buds. On the direct or immediate action of tlte Male Element on the Mother Form.-·Another remarkable class of facts must be here considered, because they have been supposed to account for some cases of buJ.-variation: I refer to the direct action of the male element, not in the ordinary way on the ovules, but on certain parts of the female plant, or in the case of animals on the subsequent progeny of the female by a second male. I may premise that with plants the ovarium and the coats of the ovules are obviously parts of the female, and it could not have been anticipated that they would be affected by the pollen of a foreign variety or species, although the development of the embryo, within the embryonic sack, within the ovule, within the ovarium, of course depends on the male element. Even as long ago as 1729 it was observed nR that white and blue varieties of the I ea, when planted ncar each other, mutually crossed, no doubt through the agency of bees, and in the autumn blue and white peas were found within the same pods. Wiegmann made an exactly similar ob. crvation in the present century. The same result has followed several times when a variety with peas of one colour has been artificially crossed Ly a differently-coloured variety.117 These statements led Gartner, who was highly scept ical on the subject, carefully to try a long series of experiments : he selected the most constant varieties, and the result conclusively showed that the colour of the .skin of the pea is modified when pollen of a differently coloured variety is used. This conclusion has since been confirmed by experiments made by the Rev. J. :rvr. BerkeleyY8 l\1r. Laxton of Stamford, whilst making experiments on peas for the express purpose of ascertaining the influence of foreign pollen on the motherplant, bas reccntly 110 observed an important additional fact. He fertilised the Tall Sugar pea, which bears very thin green pods, becoming brownish- 116 'Philosopl1icn.l Transact .,' vol. xliii., 1714-45, p. 525. 117 'lVIr. Swnyne, in 'Transac t. IT ort. Soc.,' vol. v. p. 234; and Gartner, 'Bas-tarrlcrzcugung,' 1849, s. 81 anrl 409. llR ' Gard. Chron.,' 1854, p. 40-!. 119 Ibiu., 18GG, p. 900. |