0. 12] 



CLASSIFICATION AND DESCRIPTION 



73 



thinner and rather pubescent beneath. Fruit globose, in. broad, 

 on a bract usually quite rounded at base. 



This is usually considered as a variety of the last-named species. 

 It is found from New York south and west. 



3. Tilia heteroph^lla, Vent. (WHITE 

 BASSWOOD.) Leaves large, often 8 in. 

 broad, smooth and bright green above, 

 silvery white and downy beneath, with 

 darker, purplish veins. A large tree ; 

 wild in Pennsylvania, west and south, and 

 often cultivated. 



T. heteroph^lla, 



4. Tilia Europe&a, Mill. (EUROPEAN LINDEN.) 

 Leaves twice as long as the petioles, and smooth ex- 

 cept a woolly tuft in the axils of the veins beneath. 

 Small and large leaved varieties are in ciiltivation. 

 The flowers have no petal-like scales among the 

 stamens, while the American species have. An orna- 

 mental tree with dense foliage; often cultivated from 

 Europe. The twigs are more numerous and more slender than 

 those of the American species. Nearly a score of named varieties 

 are in cultivation. Var. ladniata has deeply cut and twisted leaves. 



ORDER IX. RTJTACE^J. (Rus FAMILY.) 



Shrubs and trees, rarely herbs, in most cases with 

 transparent -dotted, heavy- scented foliage. A rather 

 large order in warm climates. 



GENUS 12. XANTHOXYLUM. 



Shrubs or trees with mostly odd- 

 pinnate, alternate leaves. The stem 

 and often the leaflets prickly j flow- 

 ers small, greenish or whitish ; fruit 

 dry, thick pods, with 1 to 2 seeds. 



1. Xanthoxylum Americanum, Mill. 

 (NORTHERN PRICKLY-ASH. TOOTHACHE- 

 TREE.) Leaves and flowers in sessile, 

 axillary, umbellate clusters ; leaflets 5 to 



