690 Clethraceae; Pyrolaceae 



Fam. 157. CLETHRACEAE Ryobu Ka White Alder Family 



Trees and shrubs with simple alternate exstipulate leaves; flowers bisexual, in terminal racemes or panicles; calyx 5-parted, 

 the segments imbricate in bud, persistent; corolla lobes 5, free, imbricate in bud; stamens 10-12, free, the anthers reflexed in 

 bud, sagittate, opening by pores; disc absent; ovary superior, 3-locular; style solitary, 3-lobed; ovules many, the placentae axile; 

 capsules globose, loculicidally dehiscent, 3-valved, the axis persistent; seeds many, flat or 3-angled, sometimes winged; endo- 

 sperm fleshy, the embryo cylindric. Two genera, with about 30 species, in e. Asia, N. America, and Madeira. 



1. CLETHRA L. Ryobu Zoku 



Evergreen or deciduous trees or shrubs, usually stellate-pubescent; leaves short-petiolatej usually toothed; flowers white or 

 pink. About 30 species, in N. America, e. Asia, and Madeira. 



1. Clethra barbinervis Sieb. & Zucc. C. \awadana tufted, the lateral nerves 8 to 15 pairs; inflorescence 8-15 cm. 

 Yanagita; C. barbinervis var. \awadana (Yanagita) Hara; C. long, more or less paniculate, many-flowered, densely stellate- 

 repens Nakai Ryobu. Deciduous tree with smooth, yel- pubescent; flowers white, pedicelled, 6-8 mm. across; calyx- 

 low-brown bark, the young branchlets glabrous or minutely segments ovate-elliptic, pilose; petals elliptic, rounded at apex, 

 stellate-pubescent; leaves herbaceous to chartaceous, alternate, irregularly minutely toothed; fruit depressed, erect, exceeding 

 often approximate toward the top of branchlets, broadly ob- the calyx, long-hairy, 4-5 mm. across; seeds elliptic, flat, about 

 lanceolate to narrowly cuneate-obovate, abruptly acuminate 1 mm. long, narrowly margined, with raised reticulations on 



to acute, acutely toothed, green and glabrous or sparingly the surface. July-Sept. Hills and mountains; Hokkaido, 



stellate-pubescent on upper side, paler beneath and with loosely Honshu, Shikoku, Kyushu; common and very variable. 



appressed hairs, especially on the nerves, the axillary hairs Korea (Quelpaert Isl.). 



Fam. 158. PYROLACEAE Ichi-yaku-so Ka Shinleaf Family 



Small shrubs or herbs sometimes saprophytic; leaves simple, alternate, rarely verticillate or opposite, sometimes scalelike and 

 without chlorophyll, without stipules; flowers bisexual, actinomorphic, solitary or in terminal racemes or corymbs; calyx 

 5-parted, rarely absent; petals 5, sometimes 4; stamens 10, sometimes 8, the anthers opening by pores; ovary 5- or 4-locular; su- 

 perior, many-ovuled; style and stigma simple; fruit a 5- or sometimes 4-valved capsule, rarely a berry; seeds minute, numerous, 



the testa transparent, the endosperm copious. About 11 genera, with about 50 species, chiefly in the temperate regions of the 



N. Hemisphere. 



lA. Plants green; anthers opening by pores, reflexed in bud. 

 2A. Leaves radical, ovate, elliptic or depressed-orbicular, long-petiolate; capsules dehiscent from the base; herbs. 



3 A. Flowers in racemes, not fully expanded; valves of capsules with webby pubescence on margin 1. Pyrola 



3B. Flowers solitary, fully expanded; valves of capsules without webby pubescence on margin 2. Moneses 



2B. Leaves cauline, lanceolate or narrowly oblong, short-petiolate; capsules dehiscent from the apex; flowers in corymbs or umbels, not 



fully expanded; subshrubs 3. Chimaphila 



IB. Plants saprophytic, without chlorophyll, with scalelike leaves; anthers vertically dehiscent, erect in bud. 



4A. Fruit a capsule; ovary 5-locular, with axile placentae 4. Monotropa 



4B. Fruit a berry; ovary 1-locular, with parietal placentae 5. Monotropastrum 



1. PYROLA L. IcHi-YAKu-s6 Zoku 



Glabrous evergreen perennial herbs, often stoloniferous; leaves usually radical, long-petiolate, entire or toothed; flowers in 

 simple racemes on nearly naked scapes, bracteate, nodding, white, reddish or purplish, rarely yellowish; calyx persistent, deeply 

 5-parted; petals 5, not fully expanded, connivent at tip, deciduous; stamens 10, erect, the anthers reflexed in bud, 4-locular, open- 

 ing by pores; ovary globose, 5-locular; style simple, erect or descending, the stigma depressed, obsoletely 5-lobed; ovules numerous, 

 on the spongy placentae of the persistent axis, disc absent, or 10-toothed; capsules depressed-globose, 5-locular, dehiscent; seeds 



many, small, the testa produced at both ends, the endosperm fleshy. More than 20 species, in the temperate regions of the N. 



Hemisphere. 



lA. Inflorescence glabrous; flowers in loose racemes, 1-1.5 cm. across; pores of anthers short-tubulose; disc absent; pollen in tetrads. 

 2A. Style descending, 6-10 mm. long. 



3A. Leaves reniform-orbicular, with overlapping basal margins; scapes usually completely naked except at base; calyx-segments sub- 

 orbicular, very obtuse, much shorter than wide 1. P- renifoUa 



3B. Leaves elliptic to depressed-orbicular, scarcely cordate; scapes usually with few scalelike leaves; calyx-segments deltoid to lanceo- 

 late, acuminate to acute, longer or as long as wide. 

 4A. Calyx-segments deltoid or ovate-deltoid, as long as to only slightly longer than wide; slender plants with few-flowered scapes. 

 5A. Leaves depressed-orbicular, slightly shorter than wide; bracts lanceolate, only slightly longer than to nearly as long as the 



pedicel 2. P. nephrophylla 



5B. Leaves elliptic, slightly longer than wide; bracts broadly linear, slightly shorter to slightly longer than the pedicel. 3. P. alpina 

 4B. Calyx -segments broadly lanceolate, 2J4-4 times as long as wide; stouter plants sometimes with 10-flowered scapes. 



