TREES AND SHRUBS. 



TETRAZYGIA. 



(Melastomacese.) 



Tetrazygia, A. Richard ex De Candolle, Prodr. iii. 172 (1828).— Meissner, Gen. 112. — Ben- 



tham & Hooker, Gen. i. 762. — Engler & Prantl, Pflanzenfam. iii. pt. vii. 187. 

 Antheryta, Rafinesque, Sylva Tellur. 95 (1838). 

 Lomanthera, Rafinesque, Sylva Tellur. 96 (1838). 

 Natjdinia, A. Richard, Ess. Fi. He Cub. 561 (1845). 

 Harrera, Macfadyen, Fl. Jam. ii. 60 (1850). 

 Chitonia, Don ex Naudin, Ann. Sci. Nat. ser. 3, xv. 339 (1851). 

 Miooniastrum, Naudin, Ann. Sci. Nat. ser. 3, xv. 341 (1851). 



Trees or shrubs with watery juices and terete branchlets. Leaves opposite, petiolate, oblong- 

 ovate to ovate-lanceolate, entire or denticulate, three- to five-nerved, persistent, furfuraceous like 

 the young branchlets, panicles and calyx-tubes; stipules wanting. Flowers perfect in many- 

 flowered terminal panicles or corymbs ; calyx-tube urceolate or globose, adnate to the ovary, the 

 limb constricted above the ovary and dilated below the apex, four- or five-lobed, the lobes short 

 or elongated ; petals four or five, inserted on the mouth of the calyx-tube, obovate, obtuse, convo- 

 lute in the bud ; stamens twice as many as the petals, equal, inserted in one series with the petals ; 

 filaments subulate ; anthers linear-subulate, erect or slightly recurved, attached at the base, two- 

 celled, opening by a minute pore at the apex, their connective not extended below the cells ; ovary 

 three- to six-celled ; style filiform, curved, exserted, surrounded at the base by a short sheath eight- to 

 ten-toothed at the apex ; ovules indefinite, minute, anatropous, sessile on axile placentae. Fruit a 

 three- or four-celled berry, crowned by the persistent tube of the calyx ; seeds numerous, minute, 

 obpyramidal, thickened and incurved at the apex ; testa coriaceous, slightly pitted ; hilum basi- 

 lar ; embryo exalbuminous ; cotyledons thick, radicle short, turned toward the hilum. 



Tetrazygia, with fourteen species, is confined to the West Indies and to southern Florida where 

 a single species has been discovered, the only tree of the great family of the Melastomacese found 

 in the United States. 



The generic name is from Terpa and tyyov, in allusion to the often four-parted flowers. 



