240 CHINESE ECONOMIC TREES 



property used in medicine as a cathartic. Other species yield dyes. jR. 

 frangula Linnseus, native of Europe, N. Africa, W. Asia & Siberia, yields 

 a wood that makes a fine grade of charcoal for the manufacture of gun- 

 powder. With rare exceptions the genus is shrubby, and is of ornamental 

 interest only. 



Rhamnus carlharlica is a favorite hedge plant in Europe. 



Rhamnus davuricus (Maxim.) Pallas. 

 (E. cathartica var dahurica Maximowicz.) 



A large spiny shrub or small tree up to 10 m. tall. Winter buds 

 scaly. Branchlets stout,' thorny and glabrous. Leaves opposite, oblong- 

 elliptic, acuminate, crenate-serrate, tapering toward the base, coriaceous, 

 glabrous and gray-green beneath, 5-10 cm. long. Flowers in few-flowered 

 'clusters, petals usually 4 (sometimes 5 or wanting). ' Fruit black, about 

 8 mm. in diameter. 



Amurland to N. China. 



Rhamnus utilis Decaisne. 



A shrub closely allied to the above. The leaves yield a green dye. 

 Widely distributed from Szechuan to Chekiang. 



Rhamnus crenatus Siebold & Zuccarini. 



Shrub 3 m. tall. Winter buds naked. Branchlets and young leaves 

 brownish pubescent ; leaves long acuminate, 5-10 cm. Flowers umbellate, 

 petals 5; peduncles shorter than the petioles. Fruit changing from red 

 to blue-black. 



Hupeh, Szechuan, Kiangsi, Chekiang to Fukien. 



ZIZIPHUS 



Deciduous or evergreen shrubs or trees. Branches rounded , armed 

 with usually unequal spines, one straight and the other curved. The 

 spines are modified stipules. Leaves alternate, entire or serrate, usually 

 appearing 2 ranked, firm, 3-5 nerved at the base, short petioled. Flowers 

 small greenish or whitish, pentamerous, in axillary cymes. Ovary 

 usually 2 (2-4) celled, free from the disk lining the calyx tubes; style 

 usually bifid. Fruit a drupe with 1-3 celled stone. 



