THE RUE FAMILY 



RUTACE^ Jussieu 



^LTHOUGH the typical genus of this family, Ruta, is composed of 

 herbaceous plants, the Garden rue {Ruta graveolens Linnaeus) being 

 its most familiar species, there are over loo genera with probably 

 looo species of trees and shrubs included in it, especially occurring 

 in tropical regions; many of these are armed with prickles. The leaves are 

 usually pinnately compound, the leaflets always dotted with pellucid oil-glands, 

 readily seen by the aid of a hand-lens. The small regular and usually perfect 

 flowers are in variously clustered cymes; there are from 3 to 5 imbricated sepals, 

 as many petals as there are sepals, and usually as many stamens, though some- 

 times more; the pistil has from 2 to 5 separate or united carpels. The fruit is 

 various in the different genera. 



Aside from the Citrus fruits, the family yields little of economic value except 

 a few drugs, most important of which are Jaborandi or Pilocarpus, the leaflets of 

 Pilocarpus microphyllus Stapf, and of P. /fltomndi Holmes, both of Brazil; Buchu, 

 the leaves of several species of Barosma from southern Africa; Angustura or 

 Cusparia bark, of the South American tree Cusparia Angustura (A. Richard) 

 Lyons, and the bark and fruits of the Prickly ashes. Bengal quince or Bael fruit, 

 JEgle Marmdos (Linnaeus) Correa is cultivated in India for its edible fruit, the 

 rind of which is also medicinal. 



The North American genera containing trees are : 



Fruit dry, a capsule or a samara. 

 Fruit a dehiscent capsule. 

 Fruit an indehiscent samara. 

 Fruit separating into 3 or 4 carpels, which are winged on the back; 



filaments glabrous. 

 Fruit winged all around; filaments haiiy. 

 Fruit pulpy, a drupe or berry. 

 Fruit a small drupe; stamens 8. 

 Fruit a large beny; stamens 20 to 60. 



I. Xanthoxylum. 



2. Helietta. 



3. Ptelea. 



4. Amyris. 



5. Citrus 



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