

1. Stomata of Fouquieria splendens nearly closed, 4 n 34m a. m. 



2. Partly open, 7 a. m. 



3. Open, noon. 



4. and 5. Stomata of Tradescantia zebrina in closed and open condition. 



All fixed by absolute alcohol, stained with Congo red, and mounted in balsam. 



