144 ACER 



A. HYBRIDUM, Spach. 



A tree ultimately 60 to 70 ft. high ; young shoots not downy, but with many 

 pale warts. Leaves three-lobed, the lobes pointing forward, with rarely two 

 additional, obscurely developed lobes at the base ; 2 to 4^ ins. wide, scarcely 

 so long ; dark dullish green and smooth above, pale dull green beneath, with 

 down only along the chief veins ; irregularly and sparsely toothed ; stalk not 

 milky, smooth, mostly shorter than the blade. Flowers yellowish, produced in 

 May along with, or after, the leaves, in panicles or racemes 3 to 5 ins. long. 

 Fruit with keys f to I in. long ; the wings nearly parallel. 



A hybrid of doubtful origin, but usually ascribed to A. Pseudoplatanus 

 crossed with A. Opalus. 



A. HYRCANUM, Fischer. 



A deciduous tree, 20 to 30 ft. high, of compact habit. Leaves five-lobed, 2 

 to 4 ms. across, bright green above, paler, rather glaucous and smooth beneath, 

 except for a patch of down at the base and along the chief veins ; stalk about 

 as long as the blade. The terminal lobes are rectangularly cut, and each has 

 several large, angular, blunt teeth ; basal pair of lobes ovate. Flowers greenish 

 yellow, produced during April in short-stalked corymbs. Fruit smooth ; keys 

 I to I in. long ; wings nearly parallel, in. wide. 



Native of the Balkan States and other parts of S.E. Europe. It is allied 

 to A. Opalus, but differs in the deeper and more angular lobing of the leaf. A 

 slow-growing tree of neat shape. 



A. INSIGNE, Boissier. 



A large deciduous tree with smooth branchlets. Leaves three- or five- 

 lobed, 3 to 6 ins. wide, and the same or rather more long ; truncate or slightly 

 heart-shaped at the base, downy beneath, especially in the axils and along the 

 veins ; margins coarsely and irregularly toothed, the teeth often rounded or 

 blunt. Flowers in erect corymbose panicles, 3 to 4 ins. long, appearing 

 towards the end of May. Fruit ultimately smooth ; keys i^ to if ins. long ; 

 wings \ to f in. wide, the pair forming an angle at 90 to 120." 



Var. VELUTINUM, Boissier, which is the commonest form of A. insigne in 

 cultivation, is distinguished from the type by the dense covering of pale brown, 

 velvety down all over the leaf beneath, and by the down on the nutlets and 

 wings. It comes from the same regions as A. insigne itself, and is, no doubt, 

 connected with it by intermediate forms. 



Native of the Caucasus and the mountains of N. Persia ; introduced to 

 cultivation by Mr Jean Van Volxem, along with A. Trautvetteri and A. 

 Volxemi. All three have been much confused with each other. A. Volxemi 

 differs in its larger leaves, usually as long or longer than they are wide, and in 

 the down being restricted to the sides and axils of the veins. A. Trautvetteri 

 resembles A. Volxemi in the distribution of down on the under-surface of the 

 leaves, but the wings of the fruits are parallel or even touching. At Kew, 

 A. insigne var. velutinum is about the latest of all trees to break into growth. 



A. JAPONICUM, Thunberg. 



(Flora Japonica, t. 144.) 



A small, bushy, deciduous tree, 20 to 30 ft. (rarely 40 to 50 ft.) in height ; 

 branchlets smooth. Leaves 2 to 5 ins. long and wide, roundish in the main, 

 but seven- to eleven-lobed, the lobes ovate or lanceolate, long-pointed, sharply 



