A tree, 80°—100° high, with a tall straight massive trunk 3°—4° in diameter, thick spreading branches forming a regular open round-topped or narrow pyramidal head, and stout branchlets orange-brown and pruinose when they first appear, becoming dark gray-brown. Bark on young trunks dark brown or almost black and deeply furrowed, becoming on old trees 1½′—2′ thick and divided into large unequally shaped plates separating on the surface into thin closely appressed light cinnamon-red scales. Wood light, soft, not strong, rather brittle, light red or often yellow, with thick lighter yellow or white sapwood; in Arizona occasionally manufactured into coarse lumber. Distribution. High cool slopes on the sides of cañons of the mountain ranges of southern Arizona at elevations between 6000° and 8000°, sometimes forming nearly pure forests; more abundant and of its largest size on the mountains of Sonora and Chihuahua. 11. Pinus palustris Mill. Long-leaved Pine. Southern Pine. [Illustration: Fig. 16] Leaves in crowded clusters, forming dense tufts at the ends of the branches, slender, flexible, pendulous, dark green, 8′—18′ long, deciduous at the end of their second year. Flowers in very early spring before the appearance of the new leaves, male in short dense clusters, dark rose-purple; female just below the apex of the lengthening shoot in pairs or in clusters of 3 or 4, dark purple. Fruit cylindric-ovoid, slightly curved, nearly sessile, horizontal or pendant, 6′—10′ long, with thin flat scales rounded at apex and armed with small reflexed prickles, becoming dull brown; in falling leaving a few of the basal scales attached to the stem; seeds almost triangular, full and rounded on the sides, prominently ridged, about ½′ long, with a thin pale shell marked with dark blotches on the upper side, and wings widest near the middle, gradually narrowed to a very oblique apex, about 1¾′ long and 7/16′ wide.