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yet milder districts of Ireland; and, at last, to sow in Middle- 
sex the seeds so saved in Devonshire or Ireland. We do not 
believe that the experiment in this form was ever tried ; and, if 
it had, we have no doubt that it would have failed ; for 
experience tells us that the constitution of plants is not 
affected by such means. On the contrary, we find, what it is 
rather disheartening to know, that the constitution natural to 
a species of plant is almost unchangeable. When we look 
around us at the cases which a half-informed person might 
regard as instances of acclimatisation by seed, we find they are 
all unfavourable to the supposition, that species may be 
rendered less tender by art. Take, for example. Kidney- 
beans, Onions, Potatoes, and Mignionette — all plants of the 
most extensive cultivation, for many years, and perpetually 
reproduced by seed : are they at this day in one single degree 
more hardy than they were in the first year of their intro- 
duction ? All experience says — no. The first frost of autumn 
destroys the Potato with as much certainty as in the days of 
its discoverer, Raleigh. 
To be sure, we are occasionally reminded of apparent 
exceptions to this, and are told that the Larch Fir was origin- 
ally treated as a greenhouse plant ; and we believe that there 
are those who infer from such a circumstance, that the Larch 
is become hardier than it was. This is, however, a mistake : 
the Larch was originally as hardy as it now is, only we did 
not know it, and put it into a greenhouse from ignorance 
of its real nature. 
But, although to acclimatise plants by seed-saving, seems 
a hopeless task, means certainly do exist of rendering half- 
hardy species less tender, and these we proceed to explain. 
One of the principle causes of the destruction of exotic plants* 
in the open air, is not so much the actual amount of cold 
to which they are exposed in our winters, as their being ill 
prepared to resist it. We know, from experience, that a low 
temperature acts injuriously upon plants in proportion to 
their watery contents ; that young shoots filled with watery 
sap perish in winter, while the old and drier branches are 
unhurt ; and that succulent herbage, of whatever kind, is 
the first to indicate the action of frost. Means therefore 
should be taken to cause an exotic to prepare itself for 
