928 



COMPOSITAE 



leaves slightly broader; florets 7-8, the corollas white. 



Mountains; Hokkaido, Honshu. Forma amplifolia 



(Kitam.) Hiyama. /. dentata var. amplifolia Kitam. 



Hana-niga-na. Corollas yellow; more common than the 

 white-flowered phase. 



Var. alpicola (Takeda) Ohwi. Lactuca thunbergii lusus 

 alpicola Takeda; L. dentata var. flaviflora subvar. alpicola 

 (Takeda) Makino; L. dentata var. alpicola (Takeda) Makino; 



/. alpicola (Takeda) Nakai Takane-niga-na. Stems low; 



leaves narrower, shorter; heads fewer, about 1 cm. long, the 



florets 6-9, yellow; achenes slightly longer. Rocky alpine 



slopes; Hokkaido, Honshu, Shikoku, Kyushu (Yakushima). 



Var. kimurana (Kitam.) Ohwi. /. \imurana Kitam.; /. 



dentata subsp. \imurana (Kitam.) Kitam. ^Kumoma-niga- 



NA. Alpine phase intermediate between var. alpicola and 



var. albiflora forma amplifolia. Forma albescens Kitam. 



Shiroeana-kumoma-niga-na. Flowers white. Alpine. 



Var. stolonifera (Kitam.) Nemoto. /. albiflora A. Gray; 

 Lactuca albiflora (A. Gray) Maxim.; L. dentata var. stolon- 

 ifera Kitam.- Hai-niga-na. Stems creeping; florets 5 in 



a head. Honshu, Shikoku, Kyushu. 



Ixeris musashiensis Makino & Hisauchi. Takasago-niga- 

 na. Alleged hybrid of /. dentata and an undetermined sec- 

 ond parent. 



7. Ixeris nipponica Nakai. Lactuca nipponica Nakai ex 



Makino & Nemoto Iso-niga-na. Perennial (?) with 



short rhizomes; stems 10-20 cm. long; radical leaves orbicular 

 or broadly ovate, sometimes obovate, rounded at apex, ab- 

 ruptly petiolate, mucronate-toothed, the blades 3-5 cm. long, 

 about 3 cm. wide; cauline leaves few, broadly ovate or orbicu- 

 lar-cordate, 3-8 cm. long, about 3 cm. wide, auriculate-clasp- 

 ing; heads about 1 cm. across, in dense interrupted corymbs, 

 yellow; involucres about 6 mm. long, the inner bracts 6-8. 

 June. Sandy beaches; Honshu (Echigo Prov.). 



8. Ixeris laevigata (Bl.) Schultz-Bip. var. lanceolata 

 (Makino) Kitam. Lactuca oldhamii Maxim.; L. dentata var. 

 lanceolata Makino; L. stenophylla Makino; /. oldhamii 

 (Maxim.) Kitam. Atsuba-niga-na. Perennial herb; 



flowering stems 20-40 cm. long, few-leaved; radical leaves ob- 

 long to lanceolate, blades 6-12 cm. long, 1-2 cm. wide, acumi- 

 nate, mucronate-toothed, acute at base, petiolate; cauline leaves 

 gradually narrowed below to a petiolelike base; inflorescence 

 many-headed; heads 8-10 mm. across, about 10-flowered; in- 

 volucres about 5 mm. long, the bracts about 8; achenes nar- 

 rowly lanceolate, 4-5 mm. long inclusive of the beak; pappus 



about 3 mm. long, brown. ^Kyushu (Oosumi and Satsuma 



Prov.). Ryukyus and Formosa. The typical phase occurs 



in the Philippines, s. China, Indochina, and Malaysia. 



9. Ixeris tamagawaensis (Makino) Kitam. Lactuca 

 tamagawaensis Makino; L. versicolor var. arenicola Makino; 



/. chinensis subsp. arenicola (Makino) Kitam. Kawara- 



niga-na. Perennial herb with tufted rhizomes; stems erect, 

 15-30 cm. long, naked or 1-leaved; radical leaves many, 

 broadly linear, 8-15 cm. long, 3-5 mm. wide, acute to acumi- 

 nate, usually entire or slightly mucronate-toothed, narrowed to 

 a short petiolelike base; heads few to rather many, pedicelled, 

 15-20 mm. across, pale yellow, 25- to 30-flowered; involucres 

 9-10 mm. long, the outer bracts somewhat unequal, the inner 

 about 10; achenes lanceolate, about 6 mm. long inclusive of the 

 beak nearly as long as the body; pappus white, 5-6 mm. long. 

 June-Aug. Waste grounds along rivers; Honshu, Kyu- 

 shu. Korea and Formosa. 



10. Ixeris chinensis (Thunb.) Nakai var. strigosa (Lev. 

 & Van't.) Ohwi. Prenanthes chinensis Thunb., pro parte; 



Lactuca strigosa Lev. & Van't. Takasago-so. Perennial 



herb; flowering stems erect, 20-40 cm. long, naked or 1-leaved; 

 radical leaves rather few, spathulate, 7-15 cm. long, 5-15 mm. 

 wide, acute to acuminate, narrowed to a rather broad petiole- 

 like base, sparsely mucronate-toothed or incised; cauline leaves 

 clasping but scarcely auriculate; heads rather many, white to 

 purplish, about 20-flowered, 2-2.5 cm. across; involucres 9-11 

 mm. long, the outer bracts nearly equal, the inner about 8; 

 achenes narrowly lanceolate, about 6 mm. long inclusive of 

 the beak slightly shorter than the body; pappus white, about 



6 mm. long. Apr.-June. Honshu, Shikoku, Kyushu. 



Korea. The typical phase occurs in China and e. Siberia. 



70. LACTUCA L. 



Aki-no-nogeshi Zoku 



Glabrous or sometimes slightly hairy annual, biennial, or perennial herbs; stems usually tall; leaves radical and cauline, alter- 

 nate, entire or coarsely toodied, sometimes pinnately cleft; cauline leaves usually auriculate-clasping; heads in panicles, sessile or 

 pedicelled; involucres tubular, the bracts few-seriate, the outer smaller; receptacle flat, glabrous; corollas ligulate, truncate, 5- 

 toothed, the tube half to as long as the limb; achenes ovate or lanceolate, distincdy flattened, narrowed at both ends, few-ribbed 



on both sides, the beak with a ring at apex; pappus-bristles many-seriate, simple, persistent or individually deciduous. About 



70 species, in temperate and warmer regions of the N. Hemisphere. 



lA. Achenes barely flattened, narrowly oblong or narrowly fusiform; perennial herbs with purplish corollas. 



2A. Heads about 1 cm. across; inner involucral bracts 7 or 8, the outer bracts much shorter than the inner, caliculelike; leaves pinnately 



divided; inflorescence pyramidal, paniculate \. L. sororia 



2B. Heads 3-3.5 cm. across; inner involucral bracts about 15, the outer bracts unequal; leaves entire or incised; inflorescence flat-topped, 



corymbiform 2. L. sibirica 



IB. Achenes distinctly flattened, elliptic; annual or biennial herbs with yellowish corollas. 

 3A. Petioles scarcely or not clasping. 



4A. Achenes elliptic or obovate-elliptic, about 5 mm. long, 2.5 mm. wide, 1-ribbed on each side; involucral bracts about 2.5 mm. 



wide 3. L. indica 



4B. Achenes obovate-oblong, about 4 mm. long, 1.5 mm. wide, 3-ribbed on each side; involucral bracts about 1.5 mm. wide. 



4. L. raddeana 

 3B. Petioles distinctly clasping, except the uppermost ones 5. L. triangulata 



1. Lactuca sororia Miq. L. polypodiifolia Franch.; Kitam.- — — Murasaki-niga-na. Perennial short rhizomatous 

 My cells sororia (Miq.) Nakai; M. sororia var. nudipes Migo; herb, sometimes with short stolons; stems erect, usually sim- 

 L. sororia var. nudipes (Migo) Kitam.; L. sororia var. glabra pie, hollow, 70-120 cm. long, glabrous; cauline leaves petiolate. 



