In considering the important question involved in the term “Clover sickness,” we would first direct attention to the fact that crop clover is a derivative plant which has been so _forced_ that it is many times larger and more juicy and succulent than the wild plant from which it sprung. This _derived_ nature (the propensity, as it were, for fattening) can only be maintained by a continuance from one generation to another of those luxuries to which the cultivated family has been accustomed; hence, then, if seed be brought from a richer soil to a poorer, or from a warmer to a colder climate, we may expect that its plants grown amid barley and drawn up during the summer would have but a poor constitution to withstand the rigours of winter; but can we in such a case say that the _land_ is clover-sick, that is, sick of growing clover? Of course the seed here supposed will grow better in one place than in another, as, for example, we have traced some American seed of broad-leaved clover grown by itself in a deep rich soil in the Vale of Gloucester, where the climate is so much milder as to be a fortnight before the elevated land of the Cotteswold Hills and producing an abundant crop; while the same forming part of a mixture of “seeds” with rye-grass and plantain on the hills, the two latter have taken possession of the soil, and the clover made no progress at all; whilst other seed, under precisely the same circumstances, has done remarkably well. That there is much reason for these conclusions will be found in the fact that the more seed we import from warmer climates the more difficult is it found to make the land produce a plant; still importation is rapidly on the increase, because warmer climates can produce seed more certainly and in greater quantity than we can at home. The difficulty of growing from foreign seed increases in proportion to the thinness of the soil and the backwardness of the climate, so that the elevated districts on the stony Cotteswolds just adverted to present, perhaps, more of the so-called clover-sick land than any other of like extent. The seed of clover, then, has become more and more pampered—more the offspring of large crops from deep alluvial soils under the tropical summer heat of the south of France and the United States, where it is grown as a self-crop and not fed merely on what the corn could not carry away; and so while this enervation, or, if preferred, this civilization, of plant has gone on, we expect its seed all at once to withstand the shock of a lower temperature with constant climatal changes and cutting winds; and if it does not succeed, we say that the land is clover-sick, when, in truth, it is the seed that sickens under these new and trying conditions. As well may we say that the Northern States sicken of the negro, because he there dies out so rapidly, or that the warm south sickens of humanity, because those who are unacclimated sicken and die there.