In quick-freeze deep-etch preparations in which cells are slam frozen the pellicle and the plasma membrane tends to be flattened. The double rings are present but only the outer ring of IMPs stand out prominently. The inside ring seems embedded more deeply into the plasma membrane’s P-face, i.e., into the cytosolic leaflet of this membrane. Three sets of rings are seen in this plate along with a parenthesis-shaped ring which is present at a docking site lacking a trichocyst. Pits appear in the rings where the rosettes were removed that remained attached to the E-face of the plasma membrane. TEM taken on 3/6/90 by R. Allen with Zeiss 10A operating at 80kV. Neg. 19,800X. Bar = 0.2µm.