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Show 398 ON TilE DIRECT ACTION OF TilE CHAP. XI. 1 dd d pea which, as 'its name white when dJ.·y, with pollen of tho P:up o-po tel 'ck ~kin becoming palo expresses, ]1 as d al· 1 c-pur·p l o pods· w1th very u ' 1 lt'vatod tho tall sugar-pea . 1 1 dl· Mr Laxton 1as cu 1 redd1sh-purp o w 1on Y· · • . hon,rd of it producing a purple during twenty years, and has n~:ords~on ~~len from tho pmplo-pod yielded pod; nevertheless~ a flow.or _f~·b ~o wl~c~ Mr. J.;axton kindly gave to mo. a pod clouded wJth ~mphs .-rclc~oth towards tho extremity of the pod, A space of about two m~ltcs U:alk :ere thus colomcd. On comparing the and. a sm~llcr space. ncar th~ s - od both pods having been first dried and colour w1th .that of :h.o pmpi~u~d to be identically tho same; and in both then soaked. m water, lt was 11 1 ·ncr immccl.:iatoly beneath tho outer the colonr was confmcd to th~ ~1° s .~~sed pod ,~ere also decidedly tldckcr skin of tho pod. Tho valve; ~b 10 ~{s of tho mother-plant, but this may and stronger than those .0 0 to~~ for I know not how far their thick-have been an accidental crrcums a~ ' . t . . , , 1l S "" . pea is a vanablc chaHte cr. . ness m tho I tt · ' 11oar- • '- 1 n .11.y at·o ]>ale crrconish-brown, tluclcly {. tl T 11 S tgar pea w 1C u '' ' o Thcpcaso •1 0 n. 1 · 1 t f dm·k ' pu- rp1 o• so IDJ·nuto" nstohovi.·· iblconlythrough a covered WJ~h ( o,.s 0 ' · . n or heard of this variety producing a ,, 1\'[. Ln,xton has never Reo ·c b lens, anu ~· r. • •. . . ,, .1 one or the peas was of a uruwrm cau-l a. but m tho mosscu pou . . d .1 'th l purp c pc ' . . d ccond was irrc"ularly clon cu WJ pa o tifnl violct-pnrplo tm.t, ~n tt s tor of the twoo coats which surround tho purple. 'l'hc colom l·JCt~1~n )1~~ ~~~poclrlcd vn,ricty when dl·y arc of a palo pea. As the. J_)Cas 0~ at :fi~·st ~1pc.ar that this rcmarlmblc change of colour grccnish-bul~, Jt wou. ·sed , od could not have ],con caused by the direct in the peas m the cro~ tl P lc pod. but when wo hear in mind that action of the P?llonh 0 10 . vu:,;crs ].1Ul'j)lC marks on its stipulcs, n.l1Cl tl . latter vn.ncty as pmp c ' . . 1 fl. l us ' .. ' that the Tall sugar-pea likcwi. c has purp c owcrs am pl~'l>lc pods' a.n~ icall minute purple dots on the peas, we can hanlly sbpulcs, and miCros;op ty the r)l'oduction of pnrplo in both parents has do bt that tho tcnu ncy o · . . t,· . . d 1 u . . d'fi ,d tl 0 colour of tho peas m ue crosse poe. in combn:uttJO~ rn.o ~l~hcsol specimens, I cros.·cd the same two varieties, After havmg ~xammc d b t not tho pods thcmRclvcs, were clouded and and the peas m ono po ' u · tl tl . . 1' ·J red in a much more conspicuous manner 1an 10 peas tinted with pmp u; l~c:; roduccd at the same time by the same plants. I may in the uncrossed ~)od.tlp t 1\,. . Lnxton cut me various other crossed peas t. as a cautwn 1ft ~ul. ••• ' · tl n~ 100 . . tl modified in colour; but tho change m 10. o sllglttly, olr cv n lgrdcab.cyc,n suspected by Mr. Laxton, to tho altered colom cases was c uc as 1a ' · 1 d , tl t lctlons Rccn through the tranRprtrcnt coats of t 10 y eas ; an aosf th1e0 ccoot yy l cd ons 'a 1· o pa• r·ts of the embryo ' these cases are not m any way rcmark~blo. t tl . s Mntthiola The pollen of one ldnd of stock T ·mncr now o 10 genu .... ' . . d tl ur. . o affects the colour of tho seeds of another kiJ:d, usc a.s ,~ sorn~tn~c~ t I give tho foll owing case the more readily,. as Gartner mot lCr-p ~n : . siatcrncnts with rcsp ct to tho stock prcvwusly made doubted sJ:;·nl:r . A well-known horticulturi.·t, Major Trevor Clarke, by other o s.crvcrs. tl . d· f the large red-flowered biennial stock informs me 100 that le sec s o .• l . by tli.IS ouservcr read before the IntcrnationoJ IIort. and 120 See a so a pnpcr · • Bot. Cungrc;;s of Loudon, lSGG. CuAr. xr. MALE ELEMENT ON 'l'ilE MOTilER FORM. 399 (llfatthiola annua; Oocardemt of the French) are light brown, and those of tho purple branching Queen stock ( M. incana) aro violet-black; and he found that, when flowers of the red stock were fertilised by pollen from the purple stock, they yielded about fifty per cent. of blaclc seeds. Ho sent mo fom pods from a red-flowered plant, two of which had been fertilised by their own pollen, and they included pale brown seed; and two which had been crossed by pollen from the purple kind, and they included seeds all deeply tinged with black. These latter seeds yielded pmplcflowcrcd plants like their father; whilst tho pale brown seeds yielded normal red-flowered plants; and Major Clarke, by sowing similar seeds, has observed on a greater scale tho same result. Tho evidence in this case of tho d:ircct action of tho pollen of one species on the colom of tho seeds of another species appears to mo conclusive. In the foregoing cases, with the exception of that of the purple-poclcled pea, the conts of the seeds alone have been af'fuctccl in colour. '\Ve shnll now soc that the ovarium it. elf, whether forming a large fleshy fmit or a mere thin envelope, may he rnodjfiod by foreign pollen, in colom, flavour, texture, size, and shape. The most remarkable instance, been. usc carefully recorded by highly competent authorities, is one of which I have seen an account in a letter written, in 18G7, by M. Naudin to Dr. IIookcr. M. Naudin states that he ltas seen fruit growing on 0/wmcctops humitis, which l1ad been fertilised by l\L Denis with pollen from the Phamix or date-palm. The fruit or drupe thus produced was twice as large as, and more elongated than, that proper to the Chn.mroropR; so that it was intermediate in these respects, as well as in texture, between the fruit of the two parents. These hybridiscd seeds germinated, and produced young plants likewise intermediate in character. This case is the more remarkable as tl10 Chammrops and Phamix belong not only to distinct genera, but in the estimation of some botanists to distinct sections of the family. Gallcsio m fertilised the flowers of an orange with pollen from the lemon; and one fruit thus produced bore a longitudinal stripe of peel having the colour, flrtvour, and other characters of tho lemon. Mr. Anderson 122 fertilised a green-fleshed melon with pollen from a scarlet-fleshed kind; in two of the fruits " a sensible change was perceptible; and four other fruits wcro somewhat altered both internally and externally." The seeds of the two first-mention d fruits produced plants partaking of the good properties of both parents. In the United States, where Cucmbitaccro are largely cultivated, it is tho popular bclicf123 that the fruit is thus directly affected by foreign pollen; and I have rcccivccl a similar statement with respect to 121 'Traite du Citrus,' p. 4.0. 122 'Transact. llort. Soc.,' vol. iv. p. 318. See also vol. v. p. G5. 123 Prof. Asa Gray, 'Proc. A cad. Sc.,' llostou, vol. iv., 18GO, p. 21. |