MAPLE FAMILY 
Stamens.—Three to seven, hypogynous ; filaments long and slen- 
der in the sterile flowers, short in the fertile. Anthers reddish, ob- 
long, two-celled ; cells opening longitudinally. 
Pistils.—In sterile flowers rudimentary ; in fertile, ovary borne on 
narrow disk, superior, downy, two-lobed, two-celled, compressed 
contrary to the dissepiment, wing-margined ; styles two, united at 
base only, long, exserted, red; ovules two in each cell, one usually 
aborts. 
Fruit.—Two samaras united forming a maple key. Borne on 
slender drooping pedicels an inch and a half to three inches long. 
Vary in length from one and one-half to three inches. Wings di- 
vergent, straight or curved, three-fourths of an inch broad, deep 
Staminate and Pistillate Flowers of Silver Maple, -4cer saccharinum. 
red or pale chestnut brown. Seed reddish brown. April, May. 
Cotyledons thin, leaf-like. Seed germinates as soon as it falls to 
the ground. 
The seed of Acer usually ripens in the autumn and germinates the fol- 
lowing spring. The seed of the two American species with precocious flowers, 
A. rubrum and A. Saccharinum, however, ripens at the end of a few weeks after 
che trees flower, and germinates at once. This isa provision, perhaps, acquired 
by these species to insure their perpetuation ; they grow in low, wet land, often 
inundated during the winter, and the seed, if it ripened in the autumn would 
often lie in the water through the winter and be in danger of losing its vitality ; 
but it reaches the ground after the water has fallen in the swamps and before 
the exposed surface of the ground has become baked by the hot sun of summer, 
that is, when it is just in the condition to insure the germination of seed. 
—CHaRLES S. SARGENT. 
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