=609. The dwarf shoots of the pine.=—The dwarf branches are all lateral on the long branches, or shoots. They are scattered over the year’s growth, and each bears a cluster of five long, needle-shaped, green leaves, which remain on the tree for several years. At the base of the green leaves are a number of chaff-like scales, the previous bud scales. While the dwarf branches thus bear green leaves, and scales, the long branches bear only thin scale-like leaves which are not green.
=610. Spore-bearing leaves of the pine.=—The two kinds of spore-bearing leaves of the pine, and their close relatives, are so different from anything which we have yet studied, and are so unlike the green leaves of the pine, that we would scarcely recognize them as belonging to this category. Indeed there is great uncertainty regarding their origin.
[Illustration: Fig. 339. Spray of white pine showing cluster of male cones just before the scattering of the pollen.]
=611. Male cones, or male flowers.=—The male cones are borne in clusters as shown in fig. 339. Each compact, nearly cylindrical, or conical mass is termed a cone, or flower, and each arises in place of a long lateral branch. One of these cones is shown considerably enlarged in fig. 340. The central axis of each cone is a lateral branch, and belongs to the stem series. The stem axis of the cone can be seen in fig. 341. It is completely covered by stout, thick, scale-like outgrowths. These scales are obovate in outline, and at the inner angle of the upper end there are several rough, short spines. They are attached by their inner lower angle, which forms a short stalk or petiole, and continues through the inner face of the scale as a “midrib.” What corresponds to the lamina of the scale-like leaf bulges out on each side below and makes the bulk of the scale. These prominences on the under side are the sporangia (microsporangia). There are thus two sporangia on a sporophyll (microsporophyll). When the spores (microspores), which here are usually called pollen grains, are mature, each sporangium, or anther locule, splits down the middle as shown in fig. 342, and the spores are set free.
[Illustration: Fig. 340. Staminate cone of white pine, with bud scales removed on one side.]