Page:Popular Science Monthly Volume 31.djvu/101

Rh is designed for some other flower, and the presence of nectar and proboscis-canals, as well as a fine landing-place for the bee, at the base of the hanging corolla, are all to secure cross-fertilization. This little species has worked out the problem in a most interesting way, and doubtless the insects have had much to do with determining these final results.

The box-elder and the silver-maple began blooming on April 16th. There is no evident relation between size of plant and extent of floral structure. Some Alpine gentians have flowers an inch long, while the balance of the plant is shorter and probably has less weight than the single blossom it bears. The most wonderful flower of all is that of Rafflesia Arnoldi, which sometimes measures nine feet in circumference and weighs fifteen pounds. These monstrous blossoms are almost without stem, being sessile (sitting) upon the branch of the vine from which as a parasite the flower derives its nourishment. In striking contrast with this obese robber the stately and independent silver-maple has inconspicuous flowers that might be readily overlooked if they did not appear before the foliage. The genus Acer, to which the silver or soft maple belongs, is very variable in this last point. Some species, like the one in hand (Acer dasycarpum, Eh.), flower before unfolding the leaves; others, like the highly prized sugar-maple, have the flowers and leaves appear at the same time; while others are laggards, and bring forth their blossoms after the leaves are fully formed and busy with their work. The same differences hold as to the time of ripening the seeds. The silver-maple has its seeds ready for the last breezes of May, and upon the large wing each little plantlet takes an airing that the thoughtful student watches with much delight. If the breeze is strong, the seed passes along with the unsteady and rapid progress of a butterfly, usually with a downward course from the tree-top, where it was borne, but sometimes it rises and hastens on, perhaps to fall on rich soil a hundred rods from the parent tree. Each of these winged fruits bears a single seed within, and as the fruit falls upon the ground the heavy end strikes first, thus bringing the root of the little plantlet in the best position for rapid development. When the fruits fall upon sod-ground, the condition that often obtains in Nature, the passing breezes play upon the uplifted wing and tend to work the heavy seed end of the fruit into the turf. Under favorable conditions the soft-maple seeds germinate at once, and, before the season closes, seedlings a foot or two in height may be produced. The late-flowering maples do not make any such progress, and seem satisfied if they simply secure a good crop of seeds. In order to test the importance of the soft-maple seeds obtaining a suitable place for germination as soon as they are mature, a quantity were gathered and stored in a dry place, where other seeds are kept. A year after they were sown in rich, moist soil, alongside of a row freshly gathered from under the same trees. None of the year-old seeds grew, while the fresh ones soon sent up their