INDUSTRIAL PLANTS 
264 
Fic. 251.—Elm-leaved Linden (Tilia ulmifolia, Linden Family, Tiliacee). 
Flowering branch. Flower, enlarged. Same, cut vertically. (Bail- 
lon.)—Tree 30 m. or more tall; bark grayish; leaves whitish beneath; 
flowers cream-color; fruit brownish. Native home, Europe. 
Fruit. Seed, entire. Same, cut 
Fig. 252.—Linden. Floral diagram. 
vertically. (Baillon.) 
Fig. 253.—Poplar, American Aspen (Populus tremuloides, Willow Family, 
Pistil- 
Salicacee). Leafy branch, }. Leaf. Staminate flower-cluster. 
late flower-cluster. Pistillate flower. Seed. (Britton and Brown.)—Tree 
about 30 m. tall; leaves with stalk flattened at right angles to the blade; 
flowers greenish; fruit dry. Native home, Northern North America, 
