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Show 18 INHERITANCE-: CHAP. XII. the same peculiar1ty, the probability is strong tha; it will be transmitted to at least some of their offspring. \\ e have seen that variegation is transmitted much :nore feebly by seed from a branch which had become vanegated through bud-van. a t 1' 0n, than f1·om plants which were var.i eg. ated as . seed-ling~. \Yith most plants the P?we.r of tr~ns1~:n~s10n notonou:.ly depends on some innate capacity m the md1v1dual: thus \ 11- morin 43 raised from a peculiarly coloured balsam some s~edlings, which all resembled their parent; but o.f these seedlmgs some failed to transmit the new character, wh1lst othe.rs transmitted it to all their descendants during several successive generations. So again with a -variety of the rose, two plants ~l~ne out of six were found by Vilmorin to be capable of transm1ttmg the desired character. The weeping or pendulous growth of trees is str?ngly inherited in some cases, and, without any assignable reason, fe~~ly m. oth~r cases. I ha1.e selected this character as an instance of capnmous mhentance, because It is certainly not proper to the parent-species, and because, both sexes being borne on the same tree, both tend to hans~t the same c~aract:r. Even supposing that there may have been in some mstances crossmg with adjoining tree of the same !':pecies, it is not probable that a~ the seedlings would ha1e been thus affected. At :r.Ioccas Court there 1S a. famo~1s weeping oak; many of its branches "are 30 feet long, and n? t~Icker m any pm·t of this length than a common rope:" this tree transnnts Its weeping character, in a greater or less degree, to all its seedlings; some of tho young oaks being so flexible that they have to be supported by prop ; others not showing the weeping tendency till about twenty years oltl.44 Mr. Rivers fertilized, a he informs me, the flowers of a new Belgian weeping thorn ( (),-atcegus oJ:ycantlza) with pollen from a crimson not-wee~ing lai'iety, and three young trees, "now six or e1en years old, show a decided tendency to be pendulous, but as yet are not so much so as the motherplant." According to Mr. MacKab/5 seedling fmm a magnificent weeping birch (Betula alba ), in the Botanic Garden at Edinburgh, grew for the fiTst ten or fifteen years upright, but then all became weepers like their parent. A peach with pendulous branches, like those of tho weeping willow, has been found capable of propagation by seecl.,~6 La tly, a weeping and almost prostrate yew (Tctxus baccatu) was found in a hedge in Shropshire; it was a male, but one branch bore female flower , and produced benies; these, 43 Verlot, 'La Production des Varietes,' 1 65, p. 32. 44 Loudon's 'Gard. Mag.,' vol. xii., 1836, p. 368. 45 Verlot, • La Product. des Varietes,' 1865, p. 9-!. 46 Bronn's 'Geschichte der Natm,' b. ii. s. 121. CrrAP. XII. INHERITANCE. 19 beillg sown, produced seventeen trees, all of which had exactly the same peculiar habit with the parent-treeY These facts, it might have been thought, would have been sufficient to render it probable that a pendulous habit would in all cases be strictly inherited. But let us look to the other side. 1\fr. MacNab4s sowed seeds of the weeping beech ( IJ'agus sylvatica ), but succeeded in raising only common beeches. 1\'l'T. Rivers, at my request, raised a number of seecllings from three distinct varieties of weeping elm; and at least one of the parent-trees was so situated that it could not have been crossed by any other elm; but none of tho young tTees, n,ow about a foot or two in height, show the least signs of weeping. Mr. Rivers formerly sowed above twenty thousand seeds of the weeping ash (Fraxinus excelsior), and not a single seedling was in the le~st degree pendulous : in Germany, M. Borchmeyer raised a thousand seedlings, with the same result. Nevertheless Mr. An~erson, of the Chelsea Botanic Garden, by sowing seed from a weepin~ ash, which wa::> found before the year 1780, in Cambridgeshire, raised several pendulous trees.49 Professor Henslow also informs me that some seedlinO's from a ~emale weeping ash in the Botanic Garden at Cambridge were ~t first a ~ttle pendulous, b~t afterwards became quite upright: it is probable tha~ this latter. tree, which transmits to a certain extent its pendulous habit, wa~ denved by a bud from the same original Cambri~geshire stock; whilst other weeping ashes may have had a distinct origin. But the crowning case, communicated to me by Mr. Rivers, which shows how capricious is. the inheritance of a pendulous habit, · is that a variety of ~nother spemes of ash (F. lentiscifoliu) which was formerly pendulous, 'now about twenty years old, has long lost this habit, every shoot bein()' ::remarkably erect; but s~e~lings formerly raised from it were perfect!; prostrate, the.stems ~ot nsmg more than two inches above the ground." Thus the weepmg vanety .of the common ash, which has been extensively propag~te~ by buds durmg a long period, did not, with 1\fr. Rivers, transmit Its char~cter to. one seeclling out of above twenty thousand ; whereas the weepmg vanety of a second species of ash which could not w~lst gro:vn in t~e same garden, retain its own weepin~ character, trans~ nntted to Its seedlmgs the pendulous habit in excess! . 1\fany.an~logou~ fact~ could be given, showing how apparently capricious IS the prmmple o~ inh.entance. All the seedlings from a variety of the Barberry ~B. ·vulgans) WI~h red leaves inherited the same character; only about one-third of the seedlmgs of the copper Beech (Fagus sylvatica) had pmple leaves. .Not one out .of a hundred seedlings of a variety of the Uemsus padus, ~th yel~ow fnut, bore y~llow fruit : one-twelfth of the seedlings of the vanety _of Gomus 1nascula, With yellow fruit, came true :5o and lastly, all the trees raiSed by my father from a yellow-berried holly (I lex aq_uifolium ), 4i Rev. W. A. Leighton, 'Flora of Shropshire,' p. 4!)7: aud Charleswortll's '1\iag. of Nat. Hist.,' vol. i., 1837 p. 30. , 48 V crlot, op. cit., p. 93. 49 For these several sta.temcnts, see Loudon's ' Garcl. MaO'azinc ' vol x 1834, pp. 408, ISO; and vol. 'ix., l83S: p. 597. 50 These statements arc taken from Alpb. De Candolle, 'Bot. Geograph.,' p.l083. c 2 |
