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A tree, with several forms distinct in foliage and habit, most of which appear to have arisen in cultivation. Bark scaling off in thin plates; furrowed and thick at the base of old trunks, variable in the different varieties.’

Young branchlets at first densely stellate-pubescent, becoming green and glabrous in summer ; brown in the second year. Leaves at first covered with dense loose white stellate pubescence on both surfaces, later nearly glabrous, the pubescence being only retained here and there, mainly on the veins and midrib of the lower surface, which is paler than the dark-green shining upper surface. Petioles at first densely stellate, white pubescent, ultimately glabrescent.

Fruiting heads several (two to seven) on the peduncle, bristly. Achenes with basal ring of rigid long hairs, similar hairs arising also along the body of the achene, the apex of which is more or less acute and ends in a long persistent style.

Seedling :? caulicle slender, about ½ inch long, surmounted by two narrow spathulate cotyledons, obtuse at the apex, tapering to a very narrow base, sessile, one-nerved, entire, glabrous, dark-green, about ⅓ inch long. First leaf resembling a petiole in shape, minute and glandular-pubescent. Second leaf spathulate-cuneate, with three teeth at the apex, alternately penninerved, two of the stronger nerves running into the teeth. Third leaf like the second, but larger. Succeeding leaves palmately five-lobed.

In summer, the oriental plane and its varieties are readily recognisable by the leaves, bark, and habit. In winter, the twigs are rounded, striate, glabrous, with numerous inconspicuous lenticels, the apex ending in a short stump, bearing an orbicular scar, marking where the tip of the branchlet fell off in summer. Leaf-scars, on prominent pulvini, almost but not completely surrounding the bud as a narrow ring, sinuous in margin, and with five groups of bundle-dots. Stipular line surround- ing the twig at the level of each leaf-scar. Base of the shoot ringed with scars,

1 Boissier states that the bark of the wild tree is rugose, and does not exfoliate, as is usually the case in cultivated trees, especially in var. acerifolia, of the origin of which he knew nothing. As there is considerable variation in the size of the scales of the bark on plane trees, it is probable that the difference noted by Boissier is individual and not varietal or specific. Var. acerifolia grows usually very fast, and scales off in much larger plates as a rule than is the case in the other varieties, which are slower in growth.

2 Cf. Lubbock, Seedlings, ii, 505, f. 653 (1892).