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Nicotiana
See list of 6 species in this genusReference: Goodspeed (1954).
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1a. Inflorescence a panicle-like thyrse [Fig. 911]
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2a. Petiole slender, not decurrent on the stem; pedicels 3–4 mm long in flower, elongating to 7 mm in fruit; basal, tubular, connate portion of the corolla (i.e., excluding the lobes) 12–20 mm long
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2b. Petiole broadly winged and shortly decurrent on the stem; pedicels 5–10 (–15) mm long in flower, elongating to 20 (–25) mm in fruit; basal, tubular, connate portion of the corolla (i.e., excluding the lobes) (30–) 35–55 mm long
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1b. Inflorescence appearing to be a raceme [Fig. 910]
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3a. Corolla mostly more than 5 times as long as the calyx, the basal, connate, tubular portion 40–120 mm long and 1.5–2.5 mm wide near its midpoint
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3b. Corolla 5 times as long as the calyx or shorter, the basal, connate tubular portion 13–100 mm long and 2–8 mm wide near its midpoint (note: corolla tube length
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4a. Corolla 50–100 mm long, the lobes ± acute, extending more than 50% of the way to the corolla opening [Fig. 910]
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4b. Corolla 18–50 mm long; the lobes broad-acute to ± truncate, extending less than 50% of the way to the corolla opening
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5a. Corolla (33–) 35–50 mm long, white to violet-tinged, with evident, broad-acute to obtuse lobes; flowering calyx 15–20 mm long; stem leaves neither claspling nor decurrent at the base; pollen yellow
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5b. Corolla 18–28 mm long, green-yellow to green, with obscure, ± truncate lobes; flowering calyx 8–10 mm long; stem leaves clasping and decurrent; pollen blue
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Each photo represents one species in this genus.