more than any two sheep in a flock, or any two peas in a pod, are precisely alike; still, for general purposes, we may say that all the buds and all the shoots from those buds are alike. To such an extent is this true that it is the general practice amongst gardeners to propagate, by means of cuttings or grafts, any particular variety they may be desirous of perpetuating, because reproduction by seed does not offer the same certainty of reproducing the particular quality required as propagation by buds does. But it now and then happens that one or more buds on a particular plant, and one or more shoots, are not like the rest, and then we have what in garden phraseology is termed a "sport," but which is more correctly styled a budvariation.

We propose to cite sundry selected illustrations of this phenomenon, with a view to show how wide the range of variation may be, and in what different ways it may manifest itself. The simplest case, because it involves no appreciable change of form, is that in which a single bud, or a collection of buds in one particular part of a plant, is more precocious in its development than the others on the same tree. Instances of this kind are not uncommon. The buds on one particular branch may be each year considerably in advance in point of development of their neighbours, and this without there being any appreciable reason, such as more perfect protection or shelter on one side than on another. Thus we have seen two shoots of red currants taken from the same branch: on the one spray the flowers were ten days earlier in point of expansion, the new shoots being as much as 6 in. in length, while on the other spray the buds were only just expanding. With reference to this point, it may be remarked that the same phenomenon occurs in the case of seedling varieties. There are certain horse-chestnuts-some of which have almost historical fame, such as the Marronnier du Vingt-Mars in the Tuileries Gardens —which are year by year several days in advance of their kind in their development. But the circumstance of the whole organism exhibiting this precocity is not so striking as is the early development of one particular branch or set of branches, as compared with the rest.

In point of size, whether increased or diminished, there is often great difference in the different branches of the same tree. For some reason or other-what, no one knows—the shoots on a particular branch, instead of lengthening as the rest do, remain stunted and dwarfed. Several curious garden varieties of firs, such as the Clanbrasilian fir, have originated in this way, and are reproduced or propagated by cuttings or grafts at the will of the gardener. The birch affords frequently illustrations of this phenomenon, in the form of those tufted agglomerations

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of contracted shoots so strikingly resembling birds' nests. similar occurrence is not uncommon in the wild cherry; and a correspondent-Mr. Webster, of the gardens, Gordon Castleinforms us that he has observed similar growths in the common laburnum, in the Wych elm, and in the Scotch fir. Sometimes the determining cause may be discovered in the shape of an insect or fungus, but in this case the unusual condition ceases with the destruction of the impeding cause, whatever it may be, and the condition cannot then be perpetuated by the art of the gardener.

Variation in the colour of certain leaves or flowers is an equally common occurrence, and is perhaps more easily understood. Each individual cell, to a large extent, lives independently of its neighbours, and the secretions it forms and deposits are very often different from those of adjoining cells. Colouring materials, especially fluid ones, are notoriously liable to be formed in isolated cells. Again, variations in colour so often depend on the mere superposition of cells containing material of different tints, that the changes met with, though striking to the eye, do not seem to indicate so complete a change as in the case of alterations of form or size. Very many of the variegated Pelargoniums, so fashionable now-a-days, have originated as "sports" from some previously existing variety. The intrinsic change between some of these varieties, even where apparently very considerable differences exist, is, in some instances, very slight.

A marked difference in the amount and quality of the pubescence is not unfrequently manifested in some of these cases of bud variation. A plant which ordinarily has its leaves and its younger branches invested with a coating of hairs (epidermal appendages), all on a sudden produces a shoot on which the leaves are destitute of such clothing, or vice versa. Some of the moss roses have originated from plain-leaved varieties in the manner just indicated.

But of all these cases the most striking are those which involve a change of form. We see, for instance, not unfrequently a particular branch bearing leaves very different from those on the rest of the tree, so different that but for their production on one and the same tree, the observer might readily take them to belong to different species. Many trees now cultivated for ornamental purposes have originated in this manner, such as the cut-leaved beech, the oak-leaved laburnum, and very many more, commonly to be found in plantations. Very often the whole "habit" or aspect of the tree is altered by these variations: thus many of the so-called "weeping trees" have sprung from a solitary branch of a tree which presented a pendulous character. Some trees, it may be remarked, naturally produce

leaves of very different forms: especially notable in this respect is the Euphrates Poplar, Populus euphratica, supposed with reason to be the willow mentioned in the Psalms. Occasionally the variation is confined to one half of the leaves. A remarkable instance of this kind has been noted by A. Braun in a species of Irina, where one half of the leaf was undivided, the other deeply gashed into narrow segments.

The history of these variations is pretty much the same in all cases. All on a sudden a tree, which heretofore has produced shoots and leaves of the usual character, emits shoots with leaves of a totally different form. If they be such as the cultivator thinks likely to serve his purpose, he takes care to propagate them by means of grafts or cuttings. Sometimes variations of this character may be reproduced by seed, but there is little certainty as to this. The same kind of variation occurs in flowers and fruits. In the former it is usually associated with distinctly recognisable alterations in the phenomena of reproduction, as in what are spoken of as dimorphic or trimorphic flowers, some instances of which have been so carefully investigated by Mr. Darwin. To this latter class of bud variation we shall do no more than make passing allusion, but there are other cases which have apparently no relation to variations in the phenomena of fertilisation or reproduction, and which are strictly analogous to those already mentioned as occurring in the leaves. Every now and then, for instance, two roses of different forms and colours will be met with on the same stalk, such as a white moss rose in association with a pink one of a different form and destitute of mossy appendages. We have in a former paper in this Journal referred to some of these cases and to the famous Cytisus Adami-a laburnum bearing yellow and purple flowers as well as leaves of different character-and have also alluded to the alleged causes of these strange phenomena, on which account it is not necessary now to do more than refer to them. What is a rare occurrence in the rose, and is only known in one or two species of laburnum, is comparatively common in the chrysanthemum. There are indeed particular varieties of this favourite autumn flower which are specially liable to produce flowers of different characters on the same branch. Generally speaking, but by no means always, the change is confined to the colour of the flower only, and colour, as we have seen, is proverbially fickle in flowers. Among commonly cultivated plants azaleas and camellias are peculiarly liable to "sport." In the former plants indeed one may often witness much variation in the shape and colour of individual blossoms, and very frequently parti-coloured flowers and others intermediate between extreme forms. In the case of the fruit similar variations occur-peaches and nectarines on the same

bough; black and white grapes in the same bunch; gooseberries of different kinds on the same bush; pears, apples, or cherries, of different shapes, colour, and flavour, on the same bough. All these are, though of course rare, yet familiar occurrences to those on the look-out for such phenomena. It is necessary in some of these cases to investigate closely to see whether or no grafting of different sorts on one stock has not taken place. No doubt some of these cases, recorded by lovers of the marvellous, were simply cases of adhesion or inoculation, but, allowing for these, there still remains a large number which cannot be explained by any such process.

The above-cited illustrations might be largely added to were it necessary to do so. Mr. Darwin's work on "Animals and Plants" contains allusions to many others, and includes many references to the literature of the subject. The horticultural journals, British as well as foreign, contain very numerous records of such cases; * but we have cited enough for our present purpose, and may now pass on to the discussion of some of the alleged causes of the phenomena in question.

It must first of all be premised that these bud variations are not necessarily to be considered as malformations. Their organisation is often perfect, they are not distorted, they are simply variations; and next, they occur not exclusively in plants that have been long subjected to cultivation, but also in wild plants. Now plants that have been long in cultivation have for the most part been hybridised or "crossed" over and over again. Thus in the case of the pelargonium, it is supposed that all the immense number of different kinds now in cultivation have originated from two or three species. These have been hybridised or crossed, their offspring has been crossed in the same way, and so in the pelargonium of the present day we have a plant which has, so to speak, a great deal of very confusedly mixed blood in it.

Bud variation is very often only a reversion-a harking back--to the characters possessed by the parent; it is the result, as the phrase goes, of a dissociation of hybrid characters, the consequence of a sort of filtration by which the constituent elements become separated from their previous admixture. This reversion may be proximate, just as you may see in a family of children that, while most of them resemble both

A list of many such instances may also be found in M. Carrière's "Production et Fixation des Variétés."

The papers of Naudin, Braun, Rejuvenescence (Cytisus Adami), and Duchartre, Note sur le Chasselas Panaché, in the "Journal de la Société impériale et centrale d'Horticulture," 1865, should be read in reference to this part of our subject.

parents, some are like the one or the other, while some again present little likeness to either parent, but reproduce the lineament of some remote ancestor. A singular illustration of this phenomenon was brought under the writer's notice by Mr. Wills, and in which two plants of pelargonium showed the characters of three separate ancestors; the exact lineage of one was not fully known, but the history of the other was definitely recorded. The plant in question presented, after the fifth generation by seed (and not till then), various branches bearing leaves undistinguishable from those of the varieties known as "Unique," "Beauty of Oulton," and "Italia Unita"-three very distinct varieties, each of which were known to have been at some time or another ancestors of the plant in question, either as furnishing pollen or as the seed-parent.

Another plant of mixed origin, after retaining its characters for three years, suddenly produced branches some of which had leaves of the form and colouration of those of "Beauty of Oulton," the original seed-parent, while the remainder were bedecked with leaves in all respects similar to those of "Lucy Grieve," the ancestral pollen or male parent. The two varieties in question are widely different. In the cases just alluded to there was not a mere change of colour-an affair of comparatively minor importance-but there was a change of configuration and substance. Other cases of a similar nature have been recorded by various observers, amongst others by Mr. Grieve, the raiser of the popular " Mrs. Pollock” pelargonium.

Of course any plant produced from seed requiring for its development the contact of the pollen tube with the ovule or the germinal vesicle must be held to have mixed characters, and more markedly so in the case of unisexual flowers, either monoecious or dioecious. From this point of view a case lately recorded by Mr. Meehan becomes very significant. That gentleman relates that he obtained cuttings from Cuphea leiantha, a diœcious plant, producing its male and female flowers on different individuals. It is not stated whether the cuttings were taken from a male or a female plant, but it is stated that some of these cuttings produced male, others female, plants, and yet all were taken from a plant of one sex only. So, too, it is well known that certain unisexual trees will in some seasons produce male flowers only, in other seasons female flowers only, and vice versâ.

To enter into questions relating to the sexuality of plants would, however, lead us too far. We merely now indicate the facts, as proofs of the composite character of the plant.

But dissociation of mixed characters will not account for all the cases of bud variation. Very often we have no evidence at