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Pollen sacs and in situ pollen grains. (A) Part of a degraded pollen sac enclosed by pubescence of tapetal tissue, 9705–37, ×42; scale bar = 240 µm. (B) Local magnification of A showing ribbed pollen mass, ×600. (C) Another pollen mass, 9705–39, ×600. (D) Showing an entire ribbed grain of C, ×1200. Scale bars in B and C = 25 µm.
