Page:TheTreesOfGreatBritainAndIreland vol02B.djvu/245



belonging to the order Coniferæ, with thick scaly bark, irregular and not whorled branches, and deciduous foliage. Branchlets of two kinds, long shoots bearing solitary leaves spirally arranged, and short shoots bearing numerous leaves in tufts at their extremities, these leaves being of unequal lengths and arising each in the axil of a bud-scale. Leaves linear, either flattened or keeled above, always strongly keeled beneath, with a single fibro-vascular bundle and two resin-canals close to the epidermis of the outer angles. Buds of three kinds: (1) terminal on the long branchlets and developing either into long or short shoots; (2) axillary on the long branchlets, scattered, solitary in the axils of the leaves, and developing occasionally into long shoots, or more commonly producing short shoots with apical tufts of leaves; and (3) apical buds on the short shoots, which usually on developing slightly prolong the short shoot and produce again a tuft of leaves, this process being repeated for several years; or occasionally suddenly elongate into long shoots with solitary leaves, or produce flowers. In this way a complicated and irregular system of branching results, very different from that produced by the regular whorled buds of pines, silver firs, and spruces.

Flowers monœcious, fertilised by the wind, arising solitary on the apices of short shoots of two to six years old. Male flowers always much more numerous than the females, directed downwards; globose, ovoid or oblong; sessile or stalked, surrounded at the base by scales, and composed of numerous stamens with short stalks spirally arranged on a central axis; anthers two-celled, dehiscing longitudinally; connective rounded. Female flowers always erect, subglobose, girt at the base by a bundle of leaves, and consisting of a series of orbicular, stalked, ovular scales, each in the axil of a much longer mucronate, oblong bract. The scales, each bearing two ovules, increase in size, as the flower develops into the fruit, while the bracts do not increase.

Fruit a cone, short-stalked and always erect, composed of concave imbricated woody scales, which are persistent and are either longer or shorter than the bracts; cones ripening at the end of the first season, the scales opening and letting out the seeds, which are distributed by the wind in autumn or in the following spring, the Rh