792 THEACEAE 



5. TRIADENUM Raf. 

 Perennial glabrons, Hupericum-like marsh herbs, with horizontal rootstocks. Leaves 

 opposite : blades elongated, thickish, punctate, with nerves conspicuously curving along the 

 margins. Flowers rather few, usually in contracted cymes. Sepals 5, erect, equal. Petals 

 5, pink to greenish purple, imbricated, not oblique, deciduous. Stamens mostly 9 : fila- 

 ments united in groups of 3's, which alternate with scale-like, orange-colored glands. 

 Ovary 3-celled, sessile. Styles 3, distinct. Ovules numerous. Capsule 3-celled, opening 

 by 3 valves at the top, surpassing the sepals. Seeds numerous. [Elodea Pursh, not 

 Michx.] Marsh St. John's-wort. 



Leaf-blades sessile, partly clasping or truncate. 



Leaf-blades broadest at the base or below the middle, partly clasping. 1. T. Virginicum. 



Leaf-blades mostly broadest above the middle, merely sessile. 2. T. lonfiifoUum. 



Leaf-blades petioled," narrowed at the base. 3. T. petiolatum. 



1. Triadenum Virginicum (L. ) Eaf. Stems 2-6 dm. tall, often sparingly branched, 

 rooting at the lower joints : leaf-blades oblong, elliptic or ovate. 2-10 cm. long, spreading, 

 rounded or emarginate at the apex, glaucous and usually black-punctate beneath, sessile, 

 the broad base clasping : cymes peduncled, few-flowered : bracts like the leaves but smaller : 

 sepals lanceolate or oblong, 5-6 mm. long, acute, pale-margined : petals obovate to ob- 

 lanceolate or nearly oblong, 8-10 mm. long, acute, delicately nerved : capsules oblong, 

 8-10 mm. long, acute, fully as long as the sepals. 



In swamps, Nova Scotia and Labrador to Manitoba, Florida and Louisiana. Summer. 



2. Triadenum longifolium Small. Stems 3-6 dm. tall, simple below the inflores- 

 cence : leaf-blades oblanceolate, oblong or elliptic, thinnish, obtuse or notched at the apex, 

 undulate, truncate or subcordate at the base, sessile : cymes terminal or axillary, few-flow- 

 ered, sessile or short-ped uncled : pedicels stout, 1-2 mm. long : sepals lanceolate or linear- 

 lanceolate, 3-4 mm. long, acuminate : capsules oblong, about 1 cm. long, acute, glabrous, 

 striate. 



In swamps and low grounds, Alabama and Florida. Summer. 



3. Triadenum petiolatum (Walt.) Britton. Stems 3-10 dm. tall, usually branched, 

 sometimes copiously leafy above : leaf-blades oblong, or elliptic-oblong, 2-15 cm. long, 

 obtuse or notched at the apex, glaucescent beneath, sparingly black-dotted, gradually or 

 abruptly narrowed into short petioles : cymes few-flowered : bracts similar to the leaves : 

 bractlets minute: pedicels 1-5 mm. long: sepals oblong or nearly so, 2-2.5 ram. long, 

 obtuse, pale-margined : petals elliptic-obovate, 4-7.5 mm. long, obtuse : capsules oblong, 

 prismatic, 8-10 mm. long, acute. 



In swamps. New Jersey to Missouri, Florida and Louisiana. Summer. 



Family 7. THEACEAE DC. Camellia Family, 



Shrubs or trees, or rarely climbing vines. Leaves alternate : blades entire, 

 toothed, or rarely digitately 3-5-foliolate : stipules wanting, or rarely minute 

 and caducous. Inflorescence commonly axillary, sometimes crow^ded into axil- 

 lary or terminal racemes or panicles. Flowers mostly perfect, regular, showy. 

 Calyx (usually subtended by several bractlets) of 5, or rarely 4-7, imbricated 

 sepals. Corolla of 5, or rarely 4-7, distinct, or somewhat united, imbricated or 

 contorted petals. Androecium of numerous stamens, or these rarely as many as 

 the petals : anthers erect or versatile, opening lengthwise, or by terminal pores. 

 Gynoecium of 3-5 united carpels. Ovary mostly 3-5-celled, sometimes partially 

 immersed in the receptacle : styles as many as the cavities in the ovary, some- 

 times united. Ovules 2-many in each cavity, erect, horizontal or pendulous, 

 anatropous, amphitropous or campylotropous. Fruit leathery or woody, dehis- 

 cent or indehiscent. Seeds few or many. Endosperm wanting or fleshy. Em- 

 bryo straight or nearly so, sometimes oblique, with flat or fluted cotyledons. 



Sepals slightly unequal : ovules 2, ascending : seeds lenticular, sometimes margined. 

 Sepals ovate, united at the base : filaments united at the base : styles united : 



capsule not beaked : seeds marginless. 1. Stuartia. 



Sepals narrowly oblong, distinct : filaments distinct : styles distinct : capsule 



long-beaked: seeds margined. 2. Malachodendron. 



Sepals very unequal : ovules 4-8, pendulous : seeds strongly angled or winged. 

 Leaf-blades membranous, deciduous : flowers nearly sessile : filaments united 



into a thick tul)e : capsule globose : seeds angled. 3. Franklinia. 



Leaf-blades leathery, persistent : flowers long-pedicelled : filaments distinct : 



capsules ovoid : seeds winged. 4. Gordonia. 



