A reddish-brown body, known as the eyespot, is usually situated near the limits of the hyaline portion, and in the protoplasm contractile vacuoles similar to those of lower animals have been occasionally detected.
Young cells ar full of cytoplasm, old cells generally contain a large vacuole or vacuoles, containing cell-sap, and with only a thin, almost invisible layer of cytoplasm on their walls.
Within the cytoplasm are found manifestations of functional activity, in the form of digestive vacuoles, granules, fat, glycogen, pigment, and foreign bodies.
W.) The substance of the bacterial cell when suitably prepared and stained shows in the larger forms a mass of homogeneous protoplasm containing irregular spaces, the vacuoles, which enclose a watery fluid.
Besides the other spaces are definite rounded or oval vacuoles with a permanent pellicular wall termed by Schutt " pusules "; these open by a duct or ducts into the longitudinal groove.