Fig. 124. Larch. A and B, young scales, showing (i) inner seed-bearing scale, and (o) outer protective one. A, side view; B, front view; C and D, old scales, C from the side, D from the front, showing how the inner scale increases more rapidly than the outer.
5. The seeds are always seen to be lying quite openly on the upper side of the scales, and are not covered in by closed carpels as they are in the flowering plants. Each of the scales (which bears its two seeds) corresponds in a way to the carpel in a flower, but there is an important difference in the fact that it leaves the seeds open. In old pine cones there seems to be only one scale to each pair of seeds, but there is really a second smaller one outside it—which is sometimes quite difficult to see. It shows better in the larch, where the outside one is much the bigger of the two in the young cones, and gradually gets left behind, as the inner scale grows very fast (see fig. 124). Notice, too, how the ripe seeds have one-sided wings, which split off from the inner scale, as you can see if the cone is not too ripe. This wing is on the seed itself, not on a fruit, as is often the case among the flowering plants. The wing helps the seed to fly, and in the late autumn (in many cases two years after it began to grow, for some pines grow very slowly) it is scattered with its brothers. If you are ever near pine trees when there has been snow, you may see it sprinkled with these winged brown seeds.
Fig. 125. Winged seed of the Pine.
6. You may never have seen a baby pine tree. If not, you must get some seeds and grow them. They grow very slowly at first, and may take six weeks to show above ground even in summer; but they are well worth waiting for. Notice how they come up (see fig. 126), and that at the beginning of their growth, as they come out from the seed, they have seven or even as many as twelve first leaves, and these leaves are really the cotyledons, as you may see by cutting a seed across. So that instead of the one or two cotyledons of the flowering family, we find in the pine family that there are many cotyledons, and that their number may vary from five to ten or more.
Fig. 126. Stages in the growth of Pine seedlings; (c) cotyledons.