SAPINDACE^E. (SOAPBERRY FAMILY.) 117 



3. ACER, Tourn. MAPLE. 



Flowers polygamo-dioecious. Calyx colored, 5- (rarely 4 - 12-) lobed or 

 parted. Petals either none or as many as the lobes of the calyx, equal, with 

 short claws if any, inserted on the margin of the lobed disk, which is either 

 perigynous or hypogynous. Stamens 3-12. Ovary 2-celled, with a pair of 

 ovules in each cell ; styles 2, long and slender, united only below, stigmatic 

 down the inside. From the back of each carpel grows a wing, converting the 

 fruit into two 1 -seeded, at length separable samaras or keys. Embryo vari- 

 ously coiled or folded, with large and thin cotyledons. Trees, or sometimes 

 shrubs, with opposite palmately -lobed leaves, and small flowers. Pedicels not 

 jointed. (The classical name, from the Celtic ac, hard.) 



* Flowers in terminal racemes, greenish, appearing after the leaves; stamens 6-8. 



1. A. Pennsylvanicum, L. (STRIPED MAPLE.) Leaves 3-lobed at 

 the apex, finely and sharply doubly serrate, the short lobes taper-pointed 

 and also serrate ; racemes drooping, loose ; petals obovate ; fruit with large 

 diverging wings. Rich woods, Maine to Minn., and southward to Va., Ky., 

 and Mo. June. A small and slender tree, with light-green bark striped 

 with dark lines, and greenish flowers and fruit. Also called Striped Dog- 

 wood and Moose-Wood. 



2. A. spicatum, Lam. (MOUNTAIN M.) Leaves downy beneath, 3- (or 

 slightly 5-) lobed, coarsely serrate, the lobes taper-pointed ; racemes upright, 

 dense, somewhat compound ; petals linear-spatulate ; fruit with small erect or" 

 divergent wings. Moist woods, with the same range as n. 1. June. A tall 

 shrub, forming clumps. 



* # Flowers in nearly sessile terminal and lateral umbellate-corymbs, greenish- 



yellow, appearing with the leaves. 



3. A. saccharinum, Wang. (SUGAR or ROCK M.) Leaves 3-5-lobed, 

 with rounded sinuses and pointed sparingly sinuate-toothed lobes, either heart- 

 shaped or nearly truncate at the base, whitish and smooth or a little downy on 

 the veins beneath ; flowers from terminal leaf-bearing and lateral leafless buds, 

 drooping on very slender hairy pedicels ; calyx hairy at the apex ; petals none ; 

 wings of the fruit broad, usually slightly diverging. Rich woods, especially 

 northward and along the mountains southward. April, May. A large and 

 handsome tree. 



Var. nigrum, Torr. & Gray. (BLACK SUGAR-M.) Leaves scarcely paler 

 beneath, but often minutely downy, the lobes wider, often shorter and entire, 

 the sinus at the base often closed. With the ordinary form ; quite variable, 

 sometimes appearing distinct. 



* # * Flowers in umbel-like clusters arising from separate lateral buds, and 



much preceding the leaves ; stamens 3-6. 



% 4. A. dasycarpum, Ehrh. (WHITE or SILVER M,) Leaves very deeply 

 5-lobed with the sinuses rather acute, silvery-white (and when young downy) 

 underneath, the divisions narrow, cut-lobed and toothed; flowers (greenish- 

 yellow) on short pedicels ; petals none ; fruit woolly when young, with large 

 divergent wings. River-banks; most common southward and westward. 

 March - April. A fine ornamental tree. 



