Fls usually 2 per stem, rounded, 77 mm wide; perianth segments very broadly ovate in outline, blunt or rounded at apex, slightly mucronate, opening with yellow tones, becoming creamy white, a little inflexed, smooth, overlapping half; the inner segments more nearly roundish, with margins wavy; corona bowl-shaped, pale lemon yellow, with mouth expanded and lightly frilled.

Named after the Saint Piran, the patron saint of tin-miners and generally regarded as the patron saint of Cornwall.