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THE FLORIST. 
We think Delphiniums Hendersoni, magnificum, andformosum, pegged 
down, would be very effective for beds, as they are more continuous 
bloomers than the other kinds, and these could be edged with Flower 
of the Day, or some rose-coloured dwarf Geranium or other suitable 
plants kept dwarf. The dwarf Dahlias, such as Crystal Palace, scarlet 
Zelinda, &c., looked well when pegged down at the Crystal Palace last 
year. Centaurea argentea, with its beautiful silvery foliage, will be 
a most valuable plant for bedding purposes, either for edges or for 
ribands; but it is very scarce yet. 
DO FRUIT TREES DEGENERATE ? 
As this question has been opened afresh, it should not be allowed 
to rest until by careful investigation sufficient evidence is collected to 
convince the most doubtful. As you solicit information from your 
correspondents, I willingly contribute my mite. 
It has never surprised me that the theory of the late Mr. Knight has 
met with many ready supporters. When orchard trees, through neglect, 
are allowed to get into a state of decay, it is an easy way of accounting 
for it, to say that the varieties are wearing out. Before Mr. Knight 
advanced his theory, it was the general belief that when a good variety 
of fruit was once originated from seed it might be continued by grafting and 
budding for ever. And this opinion is still maintained by the most 
distinguished physiologists. “Varieties,” says De Candolle, “will 
endure and remain permanent, so long as man chooses to take care of 
them, as is evident from the continued existence, to this day, of sorts, 
the most ancient of those which have been described in books. By 
negligence or through successive bad seasons, they may become diseased, 
but careful culture will restore them, to all appearance, for ever.” I at 
once admit that in the common mode of propagation, varieties are 
constantly liable to decay or become comparatively worthless; but I 
believe that this is owing not to natural limits set upon the duration of 
a variety—that it does not depend on the longevity of the parent tree, 
but upon the care with which the sort is propagated, and the nature of 
the climate or soil where the tree is grown. It is a well-established 
fact, that a seedling tree, if allowed to grow on its own root, is always 
much longer lived, and often more vigorous than the same variety when 
grafted upon another stock; and experience has always proved that in 
proportion to the likeness or close relation between the stock and the 
graft is the long life of the grafted tree. Thus a variety of Pear 
grafted upon a healthy Pear seedling, lasts almost as long as upon its 
own roots ; but when grafted on a Quince it is comparatively short 
lived: this is well known to every practical gardener. 
The apparent decay of a variety is often caused by grafting upon 
unhealthy stocks. For although grafts of very vigorous habit have 
frequently the power of renovating in some measure, or for a time, the 
health of the stock ; yet the tree, when it arrives at a bearing state, will, 
sooner or later, suffer from the diseased or feeble nature of the stock. 
