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Show 4.00 0~ TilE DIRECT ACTION OF THE CHAP. XI. the cucumber in Engln.nd. It J.S 1m own tl lat gm. pc s' hn.vc been hth ud s ·nt..f fc· ct·c d ir1 colour size and sh::tl)C: in France a Jll1lc-colourcd grap_e a 1 s JU1CC tinted by' th' e' pollen of the dark-colou· red 'I,c m· t tm. ·e r· ·, m Gc:t·many 11 1 . . . vn.ricty bore bcrn·c s wh:·t ch were affcctcu.1 b. y tl1 0 pollen o. f twtot l aqommg 111!4 A, kinds· some of the berries being only part1ally affected or roo dec · . t' s long a'g o as 175112ll it ·was ob. crvcd that, w h en diff<C• I· cntly co•]l ou·'r c vdan. e JCdS tl t lly affect each Ot 1er s , cc s, an of maize grow ncar each ?th_cr, lOY ~una . Dr Savi I~ tried the expo-this is now n. popular belief m the Urn ted Stn.tc~. d. d maize together and rimcnt with care: he sowed yellow and blac -sec e b.l 1 d 'G tl . omo of the seeds were yellow, some ::tc c, an some on 10 Ramo CI1I s . . d . rows or irrcgu mottled 127 tho differently coloured seeds bcrng arrange m - larly Mr Sabine states 12a that he has Rccn the form o_f th? nca:ly globular sec d-.c apsu.] o of .1. I ma1·y zzt·s vt' ttata "n' ltcrcd by the apphcatwn of the Mp olleJn of. anot·h er Rpcc.w s, o f w1 u .c h tho cn.p's ulc has gib.b ous · angtlhe s. 11 r. f. A nu.1 erson I-Ic nry 1:!9 0 I ·osse· d Rlwdodewlron Du.lhoustce w1th e p· o enf tho }( ]l.'uttullii which is one of the ln.rgcst-flowcrcd and no?lest ~eCl~S ~~ - ~ g~nus. Th~ largc:t pod produced. by t:lc former ·pcCI?s~ w ~h ~r:~~~c;t with its own pollen, measured 1~ mch m length and L m g ' .. tlu·ce of the pou.1 s w1 u ·c 1 1 11 a d been fertilised by polle. n o.f R. NI:rn ttu.lttt measure d 1~ m· e 11 m· 1e ng th .n.. nd no les' s th·a n. 2 inche. s m. gu· -th. 1 :J.C·r c we see the effect of foreign pollen apparent]~ confine~ to mcrca~-;mg t 1~ srzc ~f tl .· . but we must be cautim,:ts m assummg, as the followmg c11sc shlCo wosv anthuamt 'i n this instance size hn.s been di roc tl y t ransct en.•c d from. .t he male ~arcnt to the capsule of the female plant. Mr. IIcmy fcrtJ!Jsed Ambis blepharophylla with pollen of A. Soyeri, and tho pods thus produced, of which he was so kind as to send me detailed measurements and sketches, were much larger in all their dimensions than those naturally produced by either the male or female parent-species. In a future chapter we shn.ll sco 124 For the French case, see ' Proo. Hort. Soc.,' vol. i. new series, 1866, p. 50. For Germany, seeM. Jack, quoted in Henfroy's 'Botanical Gazette,' vol. i. p. 277. A case in England bas recently been alluded to by tho Rev. J. M. Berkel y before tho liort. Soc. of London.' 12s • Philosophical Transactions,' vol. xlvii. 1751-52, p. 206. I~G 'Gallusio, 'T~ooria della Riprocluzione,' 1816, p. 95. J2i It may be worth while to call attention to tho several merws by which flower~ and fruit become striped or mottl •d. Firotly, by tho uirect action of tho pollen of another vnrioty or .'pocies, as witl1 tho ahov ·-giv('ll cru;cs of onmg\'S and maize. Secondly, in oros.·ts of tho fir,.t g nemtinn, when the co loms of the two l >Hreul;; uo not readily unite, as in the cases of Mirabilis un1l Dianthus given a few pages bade 'I'Idrdly, in crossed plants or a subsequent generation, by r?version, through ei 1 her bud or scmuml gonemlwn. Fourthly, by reversion to a ohamctcr not originally gained by a cro~s, but wh!ch had long be n lost, as with wlntefioworou varieties, which we shall heroaftrr sec often become stripecl with some other colour. Lastly, there arc oases, as wbon poaches arc produced with a balf or quarter of tho frnit like a TIOctarino, in which tho change is apparently due to more varintion, through either bud or solllinal generation . 1:s ''l'ransact. llort. Soc.,' vol. v. P· Ga. L29 'Journal of IIortieulturP,' Jun. 20, 18U3, p. 4U. CHAP. XI. MALE ELEMENT ON THE MOTHER FORM. 401 that the organs ofvegetation in hybrid plants, independently of the character of either parent, arc sometimes developed to a monstrous size; and tho incn'abed size of tho pods in tho foregoing cases may bo an analogous fact. No case of the direct action of tho pollen of one variety on another is better authenticated or more remarkable than that of the common apple. The fruit hero consists of the lower part of the calyx and of the upper part of tho flower-peduncle 1so in a metamOl'phoscd condition, so that the effect of tho foreign pollen has extended even beyond the limits of the ovn.rium. Cases of apples thus affected were recorded by Bradley in the early pal't of tho Jast cm1tury; and other cases arc given in old volumes of the Philoflophical Transactions; 181 in one of these a Russoting apple and an adjoining kind mutually affected each other's fruit; and in another case a smooth apple affected a rough-coated kind. Another instance has been given 132 of two very different apple-trees growing close to each other, which bore fruit resembling each other, but only on tho adjoining branches. It is, however, almost superfluous to adduce these or other cases, after that of tho St. Valery apple, which, from the abortion of the stamens, does not produce pollen, but, being annually fertilised by the girls of the neighbom ·hood with pollen of many kinds, bears fruit," differing from each other in size, fln.vour, and coloul', but resembling in character tho hermaphrodite kinds by which they havo been fertilised." 133 I have now shown, on the authority of several excellent observers, in the case of plants belonging to widely different orders, that the pollen of one species or variety, when applied to a distinct form, occasionally causes the coats of the seeds and the ovarium or fruit, including even in one instance the calyx and upper part of the peduncle of the mother-plant, to btcome modified. Sometimes the whole of the ovarium or all the seeds are thus affected; sometimes only a certain number of the seeds, as in the case of the pea, or only a part of the ovarium, as with the striped orange, mottled grapes and maize, are thus affected. It must not be supposed that any direct or immediate effect invariably follows the use of foreign pollen : this is far from being the case; nor is it known on what conditions the result depends. Mr. Knight 134 expressly states that he has never seen 13 0 See on this head the high authority of Prof. Dooaisno, in a paper translated in' Proo. IIort. Soc.,' vol. i. now series, 1866, p. 48. 131 Vol. xliii., 1744-45, p. 525; vol. xlv., 1747-48, p. 602. 13 2 ''l'ransaot. Hort. Soc.,' vol. v. pp. 63 and 68. Puvis also has collected (' De la Degeneration,' 1837, p. 36) VOL. I. several other instances; nut It is not in all oases possible to distinguish between tho direct action of foreign pollen and bud-variations. 133 T. de Clormont-Tonnerre, in ~Mem. de la Soc. Linn. de Paris,' tom. iii., 1825, p. 164. 134 • Transact. of Hort. Soc.,' vol. v. p . 68. 2 D |