81 
ACERACEJE. (MAPLE FAMILY.) 
Leaves 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. April. — A fine ornamental tree. 
5. A. rubrum, L. (Red or Swamp Maple.) Leaves 3-5- 
lobed with the sinuses acute, whitish underneath; the lobes irregu¬ 
larly serrate and notched, acute, the middle one usually longest; 
petals linear-oblong ; flowers on very short pedicels; but the fruit on 
prolonged drooping pedicels, smooth. — Swamps and wet woods, 
everywhere. March, April. — A small tree, with reddish twigs; the 
leaves varying greatly in shape, turning bright crimson in early au¬ 
tumn ; the blossoms scarlet, or sometimes greenish-yellow. 
WEOUNBO, Mcench. Ash-leaved Maple. 
Calyx 5-cleft. Petals none. Stamens mostly 5. — Flowers 
dioecious, from lateral buds ; the sterile in clusters on capillary 
pedicels ; the fertile in drooping racemes. Leaves pinnate, with 
3 or 5 leaflets. 
1. IV. aceroides, Moench. (Acer Negundo, L.) Leaflets 
smoothish when old, very veiny, ovate, pointed, toothed; fruit 
smooth, with large rather incurved wings. — River-banks. Penn, to 
iehigan. April.— A small but handsome tree, with light-green 
twigs, and very delicate drooping clusters of small greenish flowers, 
rather preceding the leaves. Also called Box-Elder. 
Order 32. HIPPOCASTAJYACE^E. 
Trees or shrubs , with opposite digitate leaves , no stip¬ 
ules, and showy hypogynous flowers which are both un- 
symmetrical and irregular . Fruit a leathery round pod , 
2 - Z-valved, ripening 1 to 3 • very large bitter seeds like 
chestnuts . — Consists essentially of the genus 
AE S CTJETJS, L. Horse-chestnut. 
Calyx regular, 5-lobed. Petals 4, sometimes 5, more or less 
unequal, with claws. Stamens 7 (rarely 6 or 8) ; filaments long 
and slender, often unequal. Style 1 : ovary 3-celled, with 2 ovules 
in each, only one of which, or one in each cell, ripens into a seed. 
Seed with a thick and shining coat and a large and round pale 
scar, without albumen. Cotyledons very thick and fleshy, some¬ 
what crumpled and united, remaining under ground in germina- 
