Fig. 2. Micrographs of spw1-1 flowers. (A) A wild-type palea with a membranous marginal region (left) and the lemma with trichomes on the entire surface (right). (B) Scanning electron micrographs (SEM) of the abaxial, marginal region of the wild-type palea. (C) SEM of the abaxial surface of a palea-like organ of the spw1-1 flower. (D) The spw1-1 flower with three palea-like organs (arrowheads) and one carpeloid palea-like organ (arrow). (E) Apical portion of the carpeloid palea-like organ with stigmatic cells (arrow). (F) A transverse section of the spw1-1 flower with seven carpels (arrowheads) and three palea-like organs (arrows). (G) A side view of the spw1-1 flower with nucellar tissues protruding from the ovary (arrowhead). (H) A longitudinal section of the spw1-1 ovary with nucellus and degenerated embryo sac (arrowhead). (I) A transverse section of nucellar tissues of an ectopic carpel formed in whorl 3, which is completely protruding from the spw1-1 ovary without internal differentiation. nu; nucellar tissue. Bar, 1 mm in (D,F,G) and 30 µm in (A-C,E,H,I).