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Show 302 ANOMALOUS MODES CHAr. xr. by buds to tho two pnront-forms; nnd we hn.vo soon in the last chapter thnt tho sp cios in this genus often cross spontaneously. lloro is nnothor analogous, but doubtful case. A writer in the' Gardener's Chronicle' loo statoR that an /Hsculus rubicuuda in his garden yearly prodnccd on one of its bmnchcs "spikes of palo yellow flowers, smaller in size and somewhat similar in colour to those of AC. Jlava." If as tho editor believes ./hJsculus rubicundn is a hybrid descended on ono side from .//1./. jlavn, we have a case of partial reversion to one of the par~nt-forms. If as some botanists maintain, AC. 1·ub·icn11da is not a hybnd, but a n~tural pcci s, tho case is one of simple hnd-variation. . 'l'ho following facts show thttt hybrids produced fro~ seed 1~ the ordimtry way, certainly sometimes revert by buds to then parcnt-tonnR. Hybrids between TrOJHf'oln:n minu,s and nu\fns 101 at fir_st produced flowers intermediate in size, colour, and structure between thmr two parents; hut later in tho season some of these plants produced flowers in all respects like those of tho motltor-form, mingled with flowers still retaining the usual intormcJiatc condition. A hybrid Cercus between a. S7!eciosissimus and phyllauthus,lO~ plants w]Jich arc widely different in appearance, produced for tho first tln·oo years angular, five-sided stems, and then some flat stems like those of 0 . phyllanthus. Kolrcutcr also gives cases of hybrid J..~obclias and Vcrbascums, which at fir. t produced flowers of one colour, and later in tho season flowers of a different colour.103 Naudin 104 raised forty hybrids from Dat~wa lrevis fertilised by D. stmmonium; and three of these hybrids produced many capsules, ofwhich a half, or quarter, or lcRser segment was smooth and of small size like tho capsule of the pure D. lrevis, tho remaining part being spinose and of larger size like the capsule of tho pure D. strctmonium: from one of these composite capsules, plants were raised which perfectly roscmbl d both parent-forms. 'l'urning now to varieties. A seedliny apple, conjoctmod to be of crossed parentage, has been described in Franco,10~ which boars fruit, with one half brgcr than tho other, of a red colom, acid taste, and peculiar odour; tho other side being greenish-yellow and very sweet : it is said scarcely over to include perfectly developed seed. I suppose that this is not tho sumo tree with thftt which Gaudichaud 100 exhibited before tho French Institute, hearing on tho sftmo bmnch two distinct kinds of apples, one a nriuette ?'Oit,qe, and the other like a reirntte CU?1arla jal~ndtre: this double-bearing variety can be propagated by grafts, and continuos to produce both kinds; Hs origin is unknown. The Rev. J. D. La Touche sent me a colomed drawing of an apple which he brought from Canada, of which half, surrounding and including tho whole of tho calyx and tho insertion of the 100 'Garcl. Oltron.,' 1851, p. 406. 1ot Gartner, 'na~tanl erzeugung,' s. MD. It is, howev r, doubtful whether these plants should b raokeu as species or varieties. • 102 Gartner, idem, s. 550. 103 • Journal de Physique,' tom. xxiii., 1783, p. 100. 'Act. Acad. St. Peters-burglt,' 1781, part i. p. 249. 10•1 'Nouvelles Archive:; du Museum,' tom. i. p. 49. 10s L' llcrmes, Jan. 14:, 1837, quoted in Loudon's ' Gun!. 1\Iag.,' vul. xiii. p. 230. lOft 'Com pies Rend us,' tom. xx:x:iv., 1852, p. 74G. CnAP. xr. OF REPI!.ODUCTIO:N AND VARIATION. 393 footstalk, is green, tho other half being brown and of tho nature of tho pomme ff?'is apple, with tho line of scpftration between tho two halves exactly defined. Tho tree was a grafted one, and Mr. La Touche thinks that tho branch which bore this curious apple sprung from tho point of junction of tho graft and stock: had this fact been ascertained, tho ca. c would probably have come into tho small class of graft-hybrids prc:·cntly to bo given. nut tho branch may have sprung from the stock, winch no donbt was a socdung. Prof. II. Locoq, who has made a groat num bor of crosses between tho differently coloured varieties of M i1'obil is j11lrt7m/01 finds that in the scod lin ~s tho colours rarely com hinc, but form distinct stripes; or half the flower 1s of one colour and half of a different colom. Sorqo varieties rcgularly_bc_ar flowo~·s striped with yellow, white, and rod; but plants of such varJOtJOs occaswnally produce on the same root branchc with uniformly coloured flowers of all throe tints, and other branches with half-andhalf coloured flowers and others with marbled flowers. Gallesio 1os crossed reciprocally white a?d red carnations, and the seedlings wore striped; hut some of the stnpcd plants also bore entirely white and entirely red flowers. Some of those plants produced one year red flowers alone and in tho following year striped flowers; or conversely, some plants, afte; having borne for two or thTcc years strir1od flowers, would revert and boar exclusively rod flowers. It may be worth mentioning that I fertilised the P·urple Sweet-pea (Latltyrus odor-u,tus) with pollen fr·om tho light-colomod Pa·inted Lwly: seedlings rai ·od from one and tho same pod wore not intermediate in character, but perfectly resembled both parents. Later in tho summer, tho plants which had at first borne flowers identical with those of the Pa·inted Lady, produced flowers streaked and blotched with purple; showing in these darker marks a tendency to reversion to tho mother-variety. AnclTow Knight 109 fcrtiljsed two white grapes with pollen of tho Aleppo grape, which is darkly variegated both in its loaves and fruit. Tho result was that tho young scedl:ings wore not at first var~egato~, but aU became variegated during tho succeeding summer; bos1dcs thiS, many produced on tho same plant bunches of grapes which wore all black, or all white, or load-coloured striped with white, or white dotted with minute black stripes; and grar1cs of all these shades could frequently be found on tho same footstalk. In most of these cases of crossed varieties, and in some of the ca es of crossed species, the colours proper to both parents appeared in the seedlings, as soon as they first flowered, in the form of stripes or larger segments, or as whole flowers or fruit of two kinds borne on tho same plant ; and in this case the appearance of the two colonrs cannot strictly be said to be due to reversion, but to some incapaeity of fusion, leading to their 10 7 'Gcogrnph. Dot. de l'Europe,' tom. iii., 1854, p. 405; and ' Do Ia l!'Cconclalion,' 18G2, p. 302. ws 'Trnite du Citrus,' 1811, p. 45. 109 ''l'rnnsact. Linn. Soc.,' vol. ix. p. 268. |