naturally many different adaptations for securing cross-fertilization--some of them of such extreme complexity that they could hardly be included here. All the family have the characteristic pealike flowers familiar enough in the sweet pea, which have already been described and figured on page 44. In all of these stamens and pistils are hidden inside the keel, at least in the early stages of the flower. In some, such as clovers, for instance, the organs emerge from the keel, and after fertilization by insects re-enter their retreat. There are scores of different plans for securing the desired object, but the common alfalfa, with a few other related plants, has the most startling. The flower begins life with its stamens and pistils concealed within the keel, which is apparently impregnable. When a bee alights on the flower and begins work he is welcomed by a small but violent explosion. When the dust of this clears away, and it is actually dusty with pollen, the dazed bee is seen to have fertilized with almost instantaneous rapidity the stigma of the exploding flower, which springs violently out of the burst keel. This is so arranged that, as it flies out of its trap, due to the explosion touched off by the bee, it strikes the under side of the bee’s body a distinct blow, brushing off in the process the pollen nearly always found there. This pollen has come from other plants. But, as in most plants of the pea family, the stamens closely surround the stigma, but are shorter than it. When the explosion occurs, the stigma, because it is slightly longer than the stamens, is the first thing to strike the bee’s body. Already impregnated, it is then indifferent to the cloud of pollen from the stamens of its own flower, which only a fraction of a second later also strikes the bee’s body. The first flower that a bee visits cannot, of course, be cross-fertilized notwithstanding the explosion which results, no matter from what angle the bee attempts to insert its proboscis. But in this case, as the stigma is unfertilized by foreign pollen, its own performs that service. In the vast majority of cases cross-fertilization is assured by certainly the most novel of processes, and, in the rare event of the bee not being covered with foreign pollen, self-fertilization is still possible.