1. Avicennia L. 



Characters of the family. Composed of 1 1 living species, 5 varieties, and 4 fossil 

 species; one of the chief constituents of coastal mangrove belts throughout the 

 tropics and subtropics of the world. 



1. Avicennia germinans (L.) L. Black-mangrove, mangle blanco. Fig. 653. 



Shrub rarely over 1 m. tall in our area (to 16 m. in tropics); petioles 2-27 mm. 

 long, often farinaceous; leaf blades oblong or lanceolate to elliptic or obovate, 

 to 15 cm. long and 44 mm. wide, obtuse or acute at the apex, entire, acute to 

 cuneate at the base, usually grayish-mealy beneath, sometimes glabrous and punc- 

 tate; spikes to 65 mm. long and 15 mm. wide during anthesis, the axillary ones 

 usually only a single pair at the base of the terminal one and shorter than it or 

 a second pair in the next lower leaf axils; calyx lobes 3-5 mm. long, 2-3 mm. 

 wide, densely appressed-pubescent outside, glabrous within; corolla white, 1.2-2 

 cm. long, parted to about the middle, the tube equaling or shorter than the calyx, 

 practically glabrous, the lobes spreading, densely gray-pubescent outside and vel- 

 vety within; fruit obpyriform or ovate, asymmetric, to 2 cm. long and 12 mm. 

 wide, densely gray-hairy, A. nitida Jacq. 



In mangrove lagoons and along tidal shores, s. e. and s. Tex.; very variable, 

 ranging from Fla. and Tex., Berm., Bah. I. and both coasts of Mex., through W.I. 

 and C.A. to the coasts of Braz. and Peru. 



The fruits of the red mangrove, Rhizophora Mangle L. (Rhizophoraceae), of 

 southern Florida and tropical America, are commonly washed ashore (especially 

 near the mouth of the Rio Grande), where they have been known to sprout, but 

 no living plant has apparently thus far become established in Texas. This species 

 grows in habitats similar to those of the black mangrove but it is readily distin- 

 guished from that species by its aerial roots that arise from its trunk and branches, 

 its regular corolla, and the development of a conspicuous radicle to several deci- 

 meters in length. 



Fam. 116. Verbenaceae St.-Hil. Vervain Family 



Herbs, shrubs, woody vines or trees; branchlets and twigs mostly tetragonal, 

 not prominently nodose nor articulate; leaves mostly opposite, deciduous, extipu- 

 late. mostly simple, sometimes compound or 1-foliolate, the blades entire or vari- 

 ously dentate, incised or cleft; inflorescence axillary or terminal, determinate or 

 indeterminate, as cymes, racemes, spikes, panicles, thyrsi, heads or false umbels, 

 sometimes involucrate, the axillary ones mostly solitary; flowers sessile or pedi- 

 cellate, perfect or imperfect, hypogynous, sometimes heterostylous or polygamous, 

 large or small, mostly irregular, the individual ones not involucrate; calyx gamo- 

 sepalous, campanulate to tubular or salverform, persistent, usually accrescent, 

 mostly 4- (more rarely 2-, 5- or 7-) lobed or toothed or sometimes the rim sub- 

 entire; corolla regular or irregular, gamopetalous, mostly funnelform or salver- 

 form, usually with a well-developed tube with its limb 4- or 5- (rarely 7- or many-) 

 parted, often somewhat 2-lipped; stamens mostly 4 and didynamous or reduced 

 to 2, sometimes 4 or 5 and equal, inserted in the corolla tube; staminodes often 

 present; carpels mostly 2 (rarely 4 or 5), united, one sometimes aborted; ovary 

 superior, mostly compound, sessile, mostly somewhat 4-lobed. at first 2- to 5-celled 

 but almost invariably soon becoming 4- to 10-celled through formation of false 

 partitions, never with a free central placenta or columella; the axile placentae- 

 lobes each bearing 1 ovule, the unpartitioned cells 2-ovulate, partitioned cells 

 1 -ovulate; ovules anatropous and basal or hemianatropous and lateral; fruit usually 

 a dry schizocarp separating into "cocci" at maturity or less commonly a drupe 



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