Lactuca L., Sp. Pl. 2: 795. 1753; Gen. Pl. ed. 5: 348. 1754; Shi & Kilian, Fl. China @ eFloras.org 20-21: 233; Strother, Fl. North Amer. @ eFloras.org 21: 259.

Annual or perennial herbs or subshrubs. Stem usually 1, usually erect, branched distally or throughout. Leaves basal and cauline or mostly cauline (at flowering), sessile or petiolate; leaf blades variously shaped, margins entire, denticulate to pinnately lobed, faces glabrous or hairy, +/- setose. Capitula ligulate, yellow, blue or whitish, borne singly or in corymbiform or paniculiform arrays. Peduncle not inflated, sometimes bracteate; calyculi of 3-10+ bracteoles in 2-3 series, sometimes intergrading with phyllaries. Phyllaries 5-13+ in 2 or more series, glabrous or hairy, lanceolate to linear, outer phyllaries gradually longer centripetally, +/- imbricate, often about half as long as inner phyllaries or even +/- approaching them in length; inner phyllaries 3, 5 or 8, often of unequal length in fruit. Receptacle flat to convex, pitted, glabrous, epaleate. Florets 6-50+, all ligulate, bisexual. Cypselae reddish brown, tan, whitish, purplish to blackish; compressed, elliptic to oblong; beaks stout (0.1-1 mm) or filiform (2-6 mm); between 2 thicker or wider lateral ribs with 1 to many slender ribs on either side; ribs 1-9 on each face, faces often transversely rugulose, usually glabrous. Pappi persistent, white, sometimes with a faint yellow tinge, single, of slender scabrid 80-120+ bristles in 2-3+ series or double, with an additional outer row of minute hairs; borne on disc at tip of cypselae or beak.

114 species

Lactuca dissecta D. Don, Prodr. Fl. Nepal. 164. 1825; Hook. f., Fl. Brit. Ind. 3: 405. 1882; Collett, Fl. Siml. ed. 2: 284. 1921 (Reprint 1980); Dhaliwal & Sharma, Fl. Kullu Dist. 382. 1999; Kaur & Sharma, Fl. Sirmaur 384. 2004; Singh & Sharma, Fl. Chamba Dist. 418. 2006; Fl. China @ eFloras.org 20-21: 234

Annual herb, 20-60 cm long. Stem solitary, erect, simple or divaricately branched from base, branches slender, glabrous, often patently hairy below, reddish purple. Leaves basal (radical) and cauline. Basal and lower cauline leaves short petioled with lamina 3-7 cm x 1-3.5 cm, pinnati-fid, -partite or -sect, lyrate, lateral lobes 3-6 pairs with additional smaller lobes, pointed downwards, rhombic, flabelliform or orbicular, apex rounded to acute, mucronate, margin sparsely dentate; terminal lobe broadly rhombic or orbicular, apex acute or obtuse. Upper stem leaves with half- amplexicaul base, lanceolate to linear-lanceolate, smaller, less or not divided, apex acuminate; both surfaces sparsely scabridulous. Synflorescence corymbiform with few to many capitula. Capitula ligulate, 8-9 mm long and 6-7 mm across, blue, with 15-20 bisexual ligulate florets; peduncle capillaceous, usually longer than capitulum, ca. 1.3 cm long, with or without bracts. Involucre narrowly cylindric and 6-7 mm across at anthesis (about 1.3 cm long in closed capitula) and longish ovoid. Phyllaries ca. 12-15 in 4-5 series, abaxially purplish red, glabrous, apex acute; outer phyllaries (3-4 series) 2-9 mm long, linear-lanceolate, approaching inner phyllaries to 3/4 their length; inner phyllaries ca. 5, 11-12 mm long; phyllaries reflexed in anthesis and deflexed in fruiting. Receptacle convex, pitted, glabrous, epaleate. All florets ligulate, blue to bluish purple, bisexual, ca. 8 mm long. Corolla blue to bluish purple; tube ca. 3 mm long, very narrow cylindrical at base; limb ca. 4 mm x 1 mm, 5-toothed. Stamens 5; anthers with 2 appendages at base. Ovary ca. 0.5 mm long; style 5 mm long, branched, branches hairy near apex. Cypsela body pale brown to blackish, obovoid, ca. 2.5 mm x 1 mm, compressed with 3 ribs on either side; beak white, filiform, 4-4.5 mm; pappus persistent, white, single of scabrid 80-120+ bristles in 2-3 series, 3-3.5 mm long.

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