Clovers are admitted by all to be such important adjuncts to the fodder plants of the farm as to render a scientific and practical treatise upon them and their allies a matter not only of interest, but of general agricultural utility; for, if we except the grasses, perhaps no natural order of plants is of greater value to the farmer than that to which the clovers belong; for, though they differ in every point of their structure, yet in their farm products they offer an interesting analogy. Thus, whilst in the Graminaceous plants we have cereal or corn-seed products, and meadow and pasture herbs, in the Leguminous plants we have a seed-producing group termed pulse, and a herb-growing green-food or fodder series. On either hand, in both groups, there are differently-cultivated forms; for, while the grass-cereals are wholly the result of arable culture, the fodder grasses are for the most part grown under conditions distinguished by the farmer as pasture. So of leguminous plants, pulse, such as peas and beans, belongs exclusively to the arable part of the farm; but the fodder kinds, as clover, either mix with the grass of the meadow, or are grown by themselves or with grasses in shifting green crops: indeed, it is by reason of clovers eking out grass, or being used as pasturage, that they have come to be designated “artificial grasses.” The tribe of plants under review forms an exceedingly natural group, which has been named _Papilionaceæ_, from the fancied resemblance in the arrangement of its flowers to the form and varied colouring of butterflies: by others it is designated _Leguminosæ_ from the two-valved seed-pod, which by the botanist is termed a _legume_,—most perfect examples of which are seen in the fruits of our more ordinary pea and bean. Though the flowers of the group are infinitely varied in size and in colour, yet they afford most permanent characters in their irregular petals, which, after all, have the same parts in the variously coloured and showy sweet-pea as in the most minute clover; so that, once examine the pea or bean, and the significance of the name of the order depending upon the flowers, will be easily understood. Again, varied as is the seed-pod, yet a little examination will show that its type is simple, there being no structural difference between the straight legume of the pea and the spirally-twisted one of the lucerne and medicks, or the many-seeded smooth pod of the common broom and the single-seeded wrinkled pod of the sainfoin.