Abstract
A glycogen-containing plastid has been found in the cells of Müllerian bodies on Cecropia peltata (Moraceae) trees. Plastids in cells of the leaf blade, petiole, and stem are of the usual chloroplast type and contain starch grains only. Müllerian bodies exist for the purpose of providing a food supply for a protective, mutualistically inhabiting ant population. A series of chemical tests and observations indicates that this glycogen is identical to animal glycogen.