FOREST TKEES. 209 



Flowers large, petals minute. Fruit black, broadly obovoid, a 

 quarter of an inch long ; three-lobed and three-seeded. A shrub 

 or tree, twenty feet high, the young branches downy. Mendo- 

 cino County, California, northward to the British Boundary. 



The common Buckthorn of Europe (R. catharticus) has been 

 so long cultivated in this country for hedges, that it has run 

 wild in many places, becoming a small tree with thorny 

 branchlets, with ovate or oblong leaves, and fruit with three to 

 four seeds. 



RHIZOPHORA, Linn. Mangrove. 



Trees or shrubs of maritime swamps, with opposite entire, 

 evergreen leaves. The branches throw out roots freely, which 

 descend and take root in the mud, each branch being supported 

 by its own roots, a single tree in this manner may extend over 

 a large space. Only one species. 



Ithi/oplioru Man^h'. Linn. Mangrove. Leaves obovate-oblong; 

 peduncles two to three flowered. Flowers pale yellow, quite 

 showy. Fruit, a small, one-seeded nut, which remains attached 

 to the tree until it germinates. A small tree, in the maritime 

 swamps of Southern Florida, Louisiana, Texas, and throughout 

 Tropical America. 



RHODODENDRON, Linn. Rose Bay. 



An extensive genus of several hundred species, widely distribu- 

 ted over the globe, mostly in cool or temperate climates. Prin- 

 cipally evergreen trees and shrubs with showy flowers, usually 

 in terminal umbels or corymbs. The Rhododendron and Azaleas 

 are so nearly allied, in fact, scarcely distinguishable as a whole, 

 that our modem botanists have classified them all under the 

 one generic name of Rhododendron, separating them under 

 sub-genera or in groups. They are all handsome, ornamental 

 shrubs or small trees, and extensively cultivated among all 

 civilized nations. We have about a half dozen species of the 

 Azalea proper, and four or at most five of the Rhododendrons, 

 but only one of the number grows tall enough to be classed 

 among trees. 



Rhododendron maxim u in, L. Great Laurel Rose Bay. Leaves 

 obovate-oblong, abrupt acute, smooth and green on both sides. 

 Flowers bell-shaped, white or pale rose color, spotted within with 

 yellow or green, and usually about an inch broad. Usually a 

 shrub from ten to twenty feet high, but in the mountains at 



