CLETHRACEAE 877 



Calyx of 2-8, often 5 partially united sepals. Corolla of 2-8, often 5, more or 

 less united petals or these occasionally distinct. Androecium of as many sta- 

 mens as there are petals or twice as many, sometimes partiallj'^ reduced to stam- 

 inodia, mostly free from the corolla. Gynoecium of several united carpels. 

 Ovary superior or inferior, 1-several-celled. Styles united. Fruit capsular, 

 baccate or drupaceous. 



stamens free and separate. 



Gynoecium superior : fruit capsular, sometime* fleshy but not truly baccate or drupaceous. 

 ' Corolla of essentially distinct petals. 



Ovary 3-celled : shrubs or trees : leaves deciduous. Fam. 1. Clethraceae. 



Ovary 4-5-celled : low evergreen herbs or saprophytes. 



Herbaceous perennials with persistent green leaves. Fam. 2. Pyrolaceae. 



Herbaceous saprophytes destitute of green leaves. Fam. 3. Monotropaceae. 



Corolla of manifestly united petals. 



Herbaceous saprophytes destitute of green leaves. Fam. 3. Monotropaceae. 



Shrubs or trees with deciduous or persistent green leaves. Fam. 4. Ericaceae. 



Gynoecium inferior : fruit baccate or drupaceous. Fam. 5. Vacciniaceae. 



Stamens adnate to the corolla-tube, or partially united into a lobed tube. 



Caulescent plants : staminodia wanting. Fam. 6. Diapenbiaceae. 



Scapose plants : staminodia present. • Fam. 7. Galaoaceae. 



Family 1. CLETHRACEAE Klotsch. White Alder Family. 



Shrubs or trees, with stellately branched pubescence. Leaves alternate, de- 

 ciduous : blades simple, often toothed, pinnately nerved. Flowers perfect, in 

 showy terminal, elongated racemes or panicles. Sepals 5, imbricated, persistent. 

 Corolla white, of 5 essentially distinct imbricated deciduous petals, these usually 

 broadest above the middle. Stamens 10. Filaments slender. Anthers sagittate, 

 inverted in anthesis : sacs opening by apical pores. Pollen of simple grains. 

 Disk obsolete. Ovary superior, 3-celled, pubescent, 3-lobed. Styles united, 

 topped by a 3-lobed stigma. Ovules numerous. Fruit a subglobose 3-lobed 

 loculicidally 3-valved capsule, the valves 2-cleft at maturity. 



1. CLETHRA L. 



Characters of the family. Pepperbush. 



Leaves glabrous or nearly so : both filaments and style glabrous. 1. C. alnifolia. 



Leaves pubescent, at least beneath : either filaments or style glabrous. 



Sepals obtuse : filaments glabrous or nearly so: style pubescent : capsules depressed. 2. C. tomentosa. 



Sepals acute : filaments pubescent : style glabrous : capsules ovoid. 3. C. acuminata. 



1. Clethra alnifolia L. A shrub 1-3 m. tall, with erect or ascending branches and 

 sparingly pubescent twigs. Leaf-blades obovate or cuneate, 3-8 cm. long, usually acute or 

 short-acuminate at the apex, sharply serrate, at least beyond the middle, glabrous or nearly 

 so on both sides, short-petioled : racemes erect, canescent, 5-15 cm. long, simple or panicu- 

 lately branched : pedicels 1-3 mm. long, subtended by narrow bracts : flowers fragrant : 

 sepals oblong or oblong-lanceolate, 2-2.5 mm. long, obtuse or sometimes acute, longitudi- 

 nally ridged in age : corolla wliite, 8-9 mm. broad : petals oblong or cuneate-oblong, 5-6 

 mm. broad, hooded and often notched at the ape.x; : filaments glabrous : style glabrous : 

 capsule subglobose, about 3 mm. in diameter, erect or ascending. 



In swamps and moist woods, Maine to New Jersey, Pennsylvania and Florida. Summer. Sweet 

 Pepperbush. White Alder. 



2. Clethra tomentosa Lam. A shrub 1-3 m. tall, with tomentose foliage, the branches 

 erect or ascending. Leaf-blades obovate, narrowly or broadly cuneate, 4-10 cm. long, acute 

 or short-acuminate, abruptly serrate, mainly above the middle, more or less pubescent 

 above, densely white-tomentose beneath, short-petioled : racemes solitary or paniculate, 

 6-15 cm. long : pedicels 2-5 mm. long, shorter than the narrow subtending bracts : flowers 

 fragrant : sepals ovate or ovate-oblong, 3-3.5 mm. long, slightly ridged in age : petals 

 white, spatulate or oblong-spatulate, 5-6 mm. long, concave above : filaments glabrous or 

 nearly so : style pubescent : capsule depressed-globose, 4-4.5 mm. broad, drooping. 



In swamps, North Carolina to Florida and Alabama. Summer. 



3. Clethra acuminata Michx. A shrub, or a small tree, with a maximum height of 

 6 m., the branches erect or rarely spreading. Leaves crowded near thee nds of branchlets ; 

 blades thinnish, oval or elliptic, 10-20 cm. long, acuminate at the apex, finely serrate 

 except the cuneate or rounded base, deep green above, paler and more or less pubes- 



