EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



441 



and with scales instead of leaves. — Ex. Monotropa, the Indian- 

 Pipe and Pinesap. 



857. In this diversified and widely diffused order, the bark and 

 foliage are generally astringent, often stimulant or aromatic from a 

 volatile oil or a resinous matter, and not seldom narcotic. Thus, the 

 leaves of Rhododendron, Kalmia, and all the related plants, are 

 deleterious (being stimulant narcotics), or suspicious. The honey 

 made from their flowers is sometimes poisonous. The Uva-Ursi 

 and the Chimaphila (Pipsissewa) are the chief medicinal plants of 



the order. The berries are generally edible, and some are largely 

 used for the dessert ; as Cranberries, Blueberries, and Huckleber- 

 ries. The fleshy calyx of Gaultheria (Checkerberry, or Winter- 

 green) has a very pleasant and well-known aroma. ]\Iany Ericaceas 

 are cultivated for ornament, especially Rhododendrons and Azaleas, 

 Heaths and Epacrises. 



FIG. 922. Pyrola chlorantha, reduced in size. 923. Enlarged flower. 924. Magnified sta- 

 men. 92.5. Pistil. 926 Cross-section of the capsule. 927. A highly magnified seed. 928. The 

 nucleu.s removed from the loose cellular testa, and divided, showing the very minute embryo. 



FIG. 929. Monotropa uniflora. 930. A petal. 931. Capsule, with the stamens. 932 Trans- 

 verse section of the same ; the thick and lobed placenta covered with very minute seeds. 



