ACERACEAE (MAPLE FAMILY) 



91 



S. trifolia. Bladder Nut. Shrub 3 m; 

 high; branches greenish, striped; leaflets 

 3, ovate, pointed. Moist thickets. May. 



ACERACEAE (Maple Family) 



Trees and shrubs icith opposite, 

 simple, usually palmately lobed leaves. 

 Small apetalous flowers and a 2-celled, 

 2-lobed ovary. 



Staphylea trifolia^ 

 Bladder nut. 



ACER 



Calyx colored, mostly 5-lobed. Petals either none, or as many 

 as the sepals. Stamens 3 to 12. Ovary 2-celled. The back of 

 each carpel develops a wing, converting the fruit into 2 i -seeded 

 samaras, or key-fruits. 



A. saccharum. Sugar Maple. A large tree; leaves 3 to s-lobed 

 with pointed sinuate-toothed lobes; flowers in nearly sessile, flat- 

 topped clusters, greenish-yellow, appearing with the leaves, drooping 

 on slender, hairy pedicels; petals none; wings of fruit broad. Rich 

 woods. April, May. 



A. saccharinum, Silver Maple. A handsome tree; leaves very 

 deeply S-lobed, with the sinuses rather acute, silvery-white beneath, 

 the divisions narrow, cut-lobed and toothed ; flowers in umbels, much 

 preceding the leaves; petals none; fruit woolly when young. River 



banks. March, April. 

 A. rubrum, Red 

 Maple. A medium- 

 sized tree with reddish 

 twigs ; leaves exceed- 

 ingly variable in shape 

 and broadly ovate or 

 suborbicular, truncate 

 or cordate at base, 

 woolly when young, 

 whitened beneath ; the 

 acuminate lobes irregu- 

 larly serrate ; petals linear-oblong ; fruit smooth on long drooping 

 pedicels. Wet woods. April. 



Acer rubrum, Ked maple. 



