608 FLORA. 



woods, Newf. to Manitoba, south to Fla. and Tex. Its sap is the main source of 

 maple sugar. April-May. 



5. Acer nigrum Michx. BLACK SUGAR MAPLE. (I. F. f. 2376.) Nearly 

 or quite as large as the Sugar Maple, with rough, blackish bark. Leaves similar, 

 but green both sides, thicker and generally more or less pubescent beneath, espe- 

 cially along the veins ; lobes much broader and shorter, with few undulations or fre- 

 quently entire, the basal sinus often narrow; samaras slightly more divergent. 

 Ont. and Vt. to Ga., Minn., La. and Ark. April-May. 



6. Acer glabrum Torr. DWARF OR ROCKY MOUNTAIN MAPLE. (I. F. f. 

 2377.) A shrub, or small tree. Leaves 2.5-7.5 cm. long, often broader, glabrous 

 on both sides, or puberulent when young, 3-5-lobed, the lobes sharply serrate; 

 flowers yellowish green, in numerous small sessile corymb-like racemes ; pedicels 

 short, glabrous; samaras glabrous, shining, 1.8-3 cm - l n g> little diverging; wing 

 8-12 mm. wide. Borders of streams and hillsides, western Neb. to Ariz., Nev. and 

 Br. Col. May. 



7. Acer Pennsylvanicum L. STRIPED OR GOOSEFOOT MAPLE. MOOSE- 

 WOOD. (I. F. f. 2378.) A small tree, the smoothish green bark striped with darker 

 lines. Leaves often 1.5-2 dm. long, broadest above the middle, thin, glabrous 

 above, sparingly pubescent beneath when young, slightly cordate or truncate at 

 at the base, 3-lobed near the apex, the lobes short and acuminate; racemes 7.5-10 

 cm. long; flowers greenish yellow, 6-8 mm. broad; petals obovate; samaras gla- 

 brous, 2.5 cm. long, widely divergent, the wing 8-10 mm. wide. In rocky woods, 

 N. S. to Lake Superior, and along the mountains to Ga. and Tenn. May-June. 



8. Acer spicatum Lam. MOUNTAIN MAPLE. (I. F. f. 2379.) A shrub, or 

 rarely a small tree, the bark green, not striped. Leaves 7.5-12.5 cm. long, gla- 

 brous above, pubescent beneath, at least when young, 3~5-lobed, the lobes acute or 

 acuminate; racemes compound, rather dense; flowers 2-3 mm. broad, greenish 

 yellow; petals linear- spatulate; samaras 1.8-2 cm. long, somewhat divergent, the 

 wing 6-8 mm. wide. Damp rocky woods, Newf. and James' Bay to Manitoba, 

 south, especially along the mountains, to N. Car., Tenn. and Minn. May-June. 



9. Acer Negundo L. Box ELDER. ASH-LEAVED MAPLE. (I. F. f. 2380.) 

 A tree. Leaves petioled, 3-5-foliolate; leaflets ovate or oval, pubescent when 

 young, nearly glabrous when old, 5-13 cm. long, 2.5-7.5 cm. wide, dentate, 

 slightly lobed or sometimes entire, acute or acuminate; flowers dioecious, droop- 

 ing, very small, appearing a little before the leaves; samaras glabrous, slightly 

 incurved, 2.5-3.75 cm. long, the broad wing finely veined. Along streams. Vt. 

 and Ont. to Manitoba, Fla. and N. Mex. Rare near the Atlantic Coast. April. 



Acer Negundo Texinum Pax. Branchlets and leaves densely pubescent. Kans. to 

 Tex. 



Acer Pseiido-Pldtanus L., the Sycamore Maple, with terminal drooping racemes of 

 yellowish flowers with very woolly ovaries, and deeply 3-5-lobed leaves, and Acer pla- 

 tanoides L., the Norway Maple, with terminal corymbs of greenish yellow flowers 

 appearing with or before the sharply 5-y-lobed leaves, are commonly planted, and have 

 occasionally escaped from cultivation in the east. 



Family 10. HIPPOCASTANACEAE T. & G. 

 Buckeye Family. 



Trees or shrubs, with opposite petioled digitately 3-o-folioiate leaves, 

 and conspicuous polygamous irregular flowers in terminal panicles. Calyx 

 5-lobed or 5-cleft in the following genus, the lobes unequal. Petals 4-5, 

 unequal, clawed. Disk entire, often i-sided. Stamens 5-8; filaments 

 elongated. Ovary sessile, 3-celled; ovules 2 in each cavity; style slender. 

 Capsule leathery, smooth or spiny, 3-celled or by abortion i-2-celled. and 

 often only i-seeded. Seeds large, shining; cotyledons very thick. The 

 family consists of the following genus, containing about 15 species, natives 

 of America and Asia, and Billia, of Mexico. 



