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senna family, represented by the Asiatic red-bud, of 

 China and Japan, and the American Judas-tree of the 

 eastern United States; in spring, before the appearance of 

 the leaves, these are profusely covered with pink or pur- 

 plish flowers. Across the transverse driveway to the 

 north, and directly on the opposite side, may be found the 

 pea family. Here are various species of the pea-tree: 

 the pigmy pea-tree, ranging from the Caucasus to Siberia 

 and Thibet; the Chamlagu pea-tree, from northern China; 

 the Chinese pea-tree; and the small-leaved pea-tree. The 

 Scotch broom and the dense-flowered broom, of Europe, have 

 representatives here; of these, the former, in Spain and 

 France attains the size of a small tree, and its wood is 

 highly prized for veneering and cabinet work; its branches 

 are extensively employed for making brooms, whence its 

 common name. Other plants of interest are the false 

 indigo, the rose acacia, and Kelsey's rose acacia, all 

 from the Southeastern United States; the tall bladder- 

 senna, from southern Europe and northern Africa; and 

 the scorpion senna, from southern Europe. Immed- 

 iately beyond is the rue family, illustrated by the hop tree 

 (Ptelea trijoliata) of the eastern United States; the prickly 

 ash, from the northeastern United States, Bunge's 

 prickly ash, from China, and the Japanese prickly ash 

 from Japan and Korea; the trifoliolate orange, from 

 northern China, which has been used as one of the 

 parents in the recent hybridization experiments by the 

 U. S. Department of Agriculture in its effort to produce a 

 more hardy orange; the lemon and forms of the orange may 

 be found in conservatory range 2, together with other woody 

 members of this family. Following this is the box family, 

 represented by a number of forms of the box-tree, from 

 Europe, Asia and Japan; the wood of the box-tree is 

 highly prized for wood-engraving, on account of its hard- 

 ness and close fine grain, and it takes a fine polish. A 

 few steps farther on is the sumac family, to which be- 

 longs the common poison ivy, so frequent in and around 



