Succulent leaves of Peperomia obtusifolia (Pipereaceae) have a photosynthetic layer that contains spherical crystal aggregates surrounded by chloroplasts with large grana. Horner conducts a detailed morphological study and determines that druses in the vacuoles of palisade cells occur below the thin pit field regions in the wall interface, suggesting an interesting physical relationship that could provide a pathway for light waves, filtered through the multiple hypodermis. The light waves pass into the palisade cells and are collected and dispersed by the druses to surrounding chloroplasts with large grana, thus creating an efficient photosynthetic system for species growing under low-light intensity conditions.
