Phase contrast and histochemical studies of the hemocytes of Periplaneta americana (L.), P. australasiae (F.), Blattella germanica (L.), Blaberus giganteus (L.), Diploptera punctata (Eschscholz), Leucophaea maderae (F.), and Nauphoeta cinerea (Olivier) showed the presence of spherule cells in all of them. Pyronin-methyl Green, Alcian Blue, and Toluidine Blue tests indicated the presence of acid mucopolysaccharides in the spherules of the spherule cells. Clusters of sperules liberated from the spherule cells seem to gradually grow in size and resemble young plasmatocytes. It is suggested that these spherules are probably precursors of new cells.