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Primula

Flowers must be fresh and fully open or well pressed flat with no wrinkles or folds to supply proper corolla width measurements.

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P. japonica
1a. Inflorescence a raceme with (2–) 3–5 whorls of flowers; corolla 19–25 mm wide
See list of 3 species in 1b
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1b. Inflorescence consisting of a solitary, terminal umbel; corolla 8–16 mm wide
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  P. veris
  2a. Corolla yellow, the basal, connate portion scarcely (if at all) exceeding the calyx; calyx 9–15 mm long, angled in cross-section; leaf blades pubescent
- See list of 2 species in 2b
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  2b. Corolla commonly pink to purple with a yellow base, the basal, connate portion longer than the calyx; calyx 3–11 mm long, ± round in cross-section (i.e., without wing-angles); leaf blades glabrous (though sometime farinose)
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    P. mistassinica
    3a. Sepals 3–6 mm long; scape 3–21 cm tall; largest leaf blades 10–40 (–60) mm long; bracts of umbel 3–6 mm long, barely (if at all) saccate at the base; capsules 2–3 mm in diameter; seeds rounded, their surface nearly smooth; flowers heterostylous
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    P. laurentiana
    3b. Sepals 6–9 mm long; scape 10–40 cm tall; largest leaf blades 40–80 mm long; bracts of umbel 6–14 mm long, definitely saccate at the base; capsules 2.5–5 mm in diameter; seeds angled, their surface evidently reticulate; flowers homostylous

Show photos of: Each photo represents one species in this genus.