RNA in situ hybridization of transverse sections of wild-type and cycloidea mutant floral buds. A through C, Wild-type flower probed with deficiens (A), cyclin D3b (B), and histone H4 (C). c, Carpels; s, functional stamens; arrowhead, arrested stamen; p, petals; s, sepals. D through F, cycloidea mutant flower probed with deficiens (D), cyclin D3b (E) probes, and a cyclin D3b sense control (F).