THE MANGROVE FAMILY 



RHIZOPHORACE^ Lindley 



HIS family consists of about 15 genera, with some 50 species of trees or 

 shrubs, many of maritime habitat, confined to the tropical and sub- 

 tropical regions of both hemispheres, probably most abundant in the 

 Old World. The wood of the larger growing trees of this family is 

 of some importance in marine construction on account of its durabihty in salt 

 water, and the astringent bark of some of them is valued for tanning; their chief 

 economic value, however, is in the habit of growth, which causes some of them 

 to protect land from the encroachments of the sea. 



Plants of the Mangrove family have an astringent bark and round twigs; their 

 leaves are usually opposite, smooth, thick and leathery, stalked and stipulate. 

 The flowers are regular and perfect, solitary or variously clustered in the axils of 

 the leaves; the calyx is persistent, 3- or 4-lobcd; corolla usually inconspicuous, its 

 petals of the same number as the divisions of the calyx; stamens two to four times 

 the number of petals, seldom only as many, inserted at the base of a more or less 

 conspicuous disk, their filaments long or short, the 2-celled anthers opening length- 

 wise; pistil of 2 to 5 united carpels, the ovary i- to 5-celled, the styles short, united, 

 the stigma various, entire or lobed; ovules pendulous, 2, 4, or rarely more in each 

 cavity. The fruit is beriy-Hke and leather}^, capped with the persistent calyx, 

 indehiscent or tardily splitting. The seeds are various. 

 There is but one species in our area. 



MANGROVE 



GENUS RHIZOPHORA LINN^US 

 Species Rhizophora Mangle Linna?us 



OMETIMES also called the Red mangrove, this tree is a characteristic 

 inhabitant of low, muddy shores, tidclands, and marshes of tropical 

 America, entering our area in southern Florida, where it forms large 

 dense thickets bordering the shores. It is said to attain its greatest 

 perfection in the streams flowing from the Everglades. Its miaximum height is 

 about 25 meters, with a trunk diameter of 1.2 meters or more. 



The bark is about 12 mm. tliick, shallowly furrowed into broad ridges and 

 scaly plates, brownish gray; internally it is red. The twigs are smooth, very stout 

 and pithy. The leaves are opposite, persistent, thick, leather}^ elhptic to obovate, 

 5 to 15 cm. long, bluntly pointed, tapering at the base into a stout stalk, entire- 



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