Abstract
The fat body of the locust Schistocerca gregaria is composed of both fat cells and oenocytes. The cells increase in number by mitotic division. Glycogen, proteins and phospholipids are present in all cells but are most abundant in the oenocytes; the amounts of these substances are less in the adult than in the immature forms, whereas uric acid is more abundant in the adult. Small mitochondria-like structures (as judged by their staining reactions to Janus Green B and acid-fuchsin-methyl green) have been observed in the cytoplasm of the fat cells, the oenocytes, the Malpighian tubules and the follicular cells of the ovary. No micro-organisms have been observed.