DIANTHUS.

It is quite common with the Sweet William (D. barbatus) to see differently coloured flowers on the same root; and I have observed on the same truss four differently coloured and shaded flowers. Carnations and pinks (D. caryophyllus, etc.) occasionally vary by layers; and some kinds are so little certain in character that they are called by floriculturists "catch- flowers." (11/53. 'Gardener's Chronicle' 1843 page 135.) Mr. Dickson has ably discussed the "running" of particoloured or striped carnations, and says it cannot be accounted for by the compost in which they are grown: "layers from the same clean flower would come part of them clean and part foul, even when subjected to precisely the same treatment; and frequently one flower alone appears influenced by the taint, the remainder coming perfectly clean." (11/54. Ibid 1842 page 55.) This running of the parti- coloured flowers apparently is a case of reversion by buds to the original uniform tint of the species.

I will briefly mention some other cases of bud-variation to show how many plants belonging to many orders have varied in their flowers; and many others might be added. I have seen on a snap-dragon (Antirrhinum majus) white, pink, and striped flowers on the same plant, and branches with striped flowers on a red-coloured variety. On a double stock (Matthiola incana) I have seen a branch bearing single flowers; and on a dingy-purple double variety of the wall-flower (Cheiranthus cheiri), a branch which had reverted to the ordinary copper colour. On other branches of the same plant, some flowers were exactly divided across the middle, one half being purple and the other coppery; but some of the smaller petals towards the centre of these same flowers were purple longitudinally streaked with coppery colour, or coppery streaked with purple. A Cyclamen (11/55. 'Gardener's Chronicle' 1867 page 235.) has been observed to bear white and pink flowers of two forms, the one resembling the Persicum strain, and the other the Coum strain. Oenothera biennis has been seen (11/56. Gartner 'Bastarderzeugung' s. 305.) bearing flowers of three different colours. The hybrid Gladiolus colvilii occasionally bears uniformly coloured flowers, and one case is recorded (11/57. Mr. D. Beaton in 'Cottage Gardener' 1860 page 250.) of all the flowers on a plant thus changing colour. A Fuchsia has been seen (11/58. 'Gardener's Chronicle' 1850 page 536.) bearing two kinds of flowers. Mirabilis jalapa is eminently sportive, sometimes bearing on the same root pure red, yellow, and white flowers, and others striped with various combinations of these three colours. (11/59. Braun 'Ray Soc. Bot. Mem.' 1853 page 315; Hopkirk 'Flora Anomala' page 164; Lecoq 'Geograph. Bot. de l'Europe' tome 3 1854 page 405; and 'De la Fecondation' 1862 page 303.) The plants of the Mirabilis, which bear such extraordinarily variable flowers in most, probably in all, cases, owe their origin, as shown by Prof. Lecoq, to crosses between differently coloured varieties.

LEAVES AND SHOOTS.

Changes, through bud-variation, in fruits and flowers have hitherto been treated of; incidentally some remarkable modifications in the leaves and shoots of the rose and Paritium, and in a lesser degree in the foliage of the Pelargonium and Chrysanthemum, have been noticed. I will now add a few more cases of variation in leaf-buds. Verlot (11/60. 'Des Varietes' 1865 page 5.) states that on Aralia trifoliata, which properly has leaves with three leaflets, branches frequently appear bearing simple leaves of various forms; these can be propagated by buds or by grafting, and have given rise, as he states, to several nominal species.

With respect to trees, the history of but few of the many varieties with curious or ornamental foliage is known; but several probably have originated by bud-variation. Here is one case:--An old ash-tree (Fraxinus excelsior) in the grounds of Necton, as Mr. Mason states, "for many years has had one bough of a totally different character to the rest of the tree, or of any other ash-tree which I have seen; being short-jointed and densely covered with foliage." It was ascertained that this variety could be propagated by grafts.

Charles Darwin

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