Page:Popular Science Monthly Volume 39.djvu/412

398 the currant, the grape, and the whortleberry, several seeds are imbedded within the fruit in a common pulpy mass; and in others, again, as in the apple, pear, quince, and medlar, they are surrounded by a quantity of spongy edible flesh. Indeed, the variety that prevails among fruits in this respect almost defies classification: for sometimes, as in the mulberry, the separate little fruits of several distinct flowers grow together at last into a common berry; sometimes, as in the fig, the general flower-stalk of several tiny one-seeded blossoms forms the edible part: and sometimes, as in the strawberry, the true little nuts or fruits appear as mere specks or dots on the bloated surface of the swollen and overgrown stem, which forms the luscious morsel dear to the human palate.

Yet in every case it is interesting to observe that, while the seeds which depend for dispersion upon the breeze are easily detached from the parent plant and blown about by every wind of doctrine, the seeds or fruits which depend for their dispersion upon birds or animals always, on the contrary, hang on to their native boughs to the very last, till some unconscious friend pecks them off and devours them. Haws, rose-hips, and holly-berries will wither and wilt on the tree in mild winters, because they can't drop off of themselves without the aid of birds, while the birds are too well supplied with other food to care for them. One of the strangest cases of all, however, is that of the mistletoe, which, living parasitically upon forest-boughs and apple trees, would, of course, be utterly lost if its berries dropped their seeds on to the ground beneath it. To avoid such a misfortune, the mistletoe-berries are filled with an exceedingly viscid and sticky pulp, surrounding the hard little nut-like seeds; and this pulp makes the seeds cling to the bills and feet of various birds which feed upon the fruit, but most particularly of the missel-thrush, who derives his common English name from his devotion to the mistletoe. The birds then carry them away unwittingly to some neighboring tree, and rub them off, when they get uncomfortable, against a forked branch the exact spot that best suits the young mistletoe for sprouting in. Man, in turn, makes use of the sticky pulp for the manufacture of bird-lime, and so employs against the birds the very qualities which the plant intended as a bribe for their kindly services.

Among seeds that trust for their dispersal to the wind, the commonest, simplest, and least evolved type is that of the ordinary capsule, as in the poppies and campions. At first sight, to be sure, a casual observer might suppose there existed in these cases no recognizable device at all for the dissemination of the seedlings. But you and I, most excellent and discreet reader, are emphatically not, of course, mere casual observers. We look close, and go to