Fig. 4. Floral development in wild type and lip1 lip2. SEMs of wild-type and lip1 lip2 flower buds at various stages of development. Differences in morphology can be detected by stage 7 (A and B), when petals in the lip1 lip2 double mutant are smaller than wild-type petals. Gaps between the petal lobes also appear to be more marked at this stage (arrows). At early stage 8 (C and D), these differences become more apparent. Towards the end of stage 8 (E and F), the furrow destined to become the lower palate and lips (arrowed) is missing in lip1 lip2. This defect is maintained throughout later stages of development (G and H, stage 10). Scale bars in (A) and (B) = 200 µm (C–F) = 500 µm and in (G) and (H) = 1 mm. Sepals have been removed in all cases.