322. AVICENNIA NITIDA BLACK MANGROVE. 39 



USES. Little use is made of the wood of this tree, though it is 

 occasionally used for fancy-work, flooring, etc. It is very durable in 

 contact with the soil and is valued in the West Indies for sills, posts, 

 etc. The bark is used for tanning purposes. 



The chief point of value in the tree is its usefulness in consoli- 

 dating the muddy shores, for which, like the Red Mangrove with which 

 it is associated, it is peculiarly adapted by the precocious germination 

 of the seed, before leaving the parent tree. When this falls into the 

 mud it quickly becomes established, undoubtedly assisted at first by the 

 retroflexed hairs of its growing radicle. Later, when grown, the 

 numerous little corky shoots from its roots hold or really make the 

 land about it. 



ORDER BIGNONIACE^: TRUMPET-CREEPER FAMILY. 



Leaves simple in the arborescent representatives in the United States mostly 

 opposite and without stipules. Flowers perfect, large, showy and more or less 

 irregular ; calyx hypogenous, bilabiate ; corolla hypogenous, somewhat bilabiate, 

 5-lobed, imbricated in the bud; stamens 2 or 4 inserted on the base of the corolla 

 with introrse 2-celled anthers longitudinally dehiscent; staminodia I or 3; ovary 

 i or 2-celled, with simple slender 2-lobed style, stigmatic at the apex ; ovules 

 numerous, anatropous and horizontal. Fruit a podlike 2-valved capsule or berry 

 and seeds without albumen. 



Trees, shrubs, climbing vines and a few exotic herbs, mostly with 

 large showy flowers, and widely distributed in tropics with a few repre- 

 sentatives in temperate regions. About 1,500 species are known, 

 grouped in nearly 100 genera. Of the 6 genera represented in the 

 United States 3 are arborescent, one of the southwestern states, 

 another of Florida and the third of the Atlantic states. 



GENUS CRESCENTIA LINNAEUS. 



Leaves alternate or clustered, persistent, short-petiolate and without stipules. 

 Floii'crs perfect, solitary or few together in the axils of the leaves, or from the 

 sides of the branchlets, with short bractiolate pedicels ; calyx 2-parted or 5-lobed, 

 leathery, deciduous ; corolla hypogenous, narrow, bell-shaped and swollen and 

 with transverse fold on the lower side, purplish or yellow streaked with purple, 

 with limb slightly oblique and 2-lipped with five irregularly toothed short lobes ; 

 stamens 4 and usually a staminodium inserted on the corolla-tube, with filiform 

 filaments and oblong spreading anther-cells; pistil with sessile i-celled ovoid-conic 

 ovary tapering into an elongated exserted style 2-lobed at the apex, the lobes 

 stigmatic on the inner faces; ovules numerous on 2 lateral placentas. Fruit 

 baccate, indehiscent, with thick firm rind and spongy placental mass containing, 

 irregularly imbedded within its substance, numerous flattened suborbicular deeply 

 grooved seeds. 



A genus of 5 or 6 species of tropical American trees distributed 

 from southern Florida and southern Mexico through the West Indies 



