The layer of contractile myonemes in Opercularia coarctata that covers most of the cytosolic side of the pellicle. Pellicular pores (the clathrin coated pits of ciliates) penetrate through this sheet. The ER is spread out against this sheet and, besides having decorated tubules, it bears thinner rails that lie between the ER and the myonemes and spindle-shaped mid pieces. For a description of these rails and mid pieces as they are found in peritrichs. Their function still remains to be determined. TEM taken on 6/7/69 by R. Allen with Philips 300 operating at 60kV. Neg. 14,800X. Bar = 0.5µm. A print of the negative was scanned and processed in Photoshop. This image is best used for qualitative analysis. A high resolution image (CIL:7331) is available for quantitative analysis. Standard glutaraldehyde fixation followed by osmium tetroxide, dehydrated in alcohol and embedded in an epoxy resin. Microtome sections prepared at approximately 75nm thickness. Additional information available at (http://www5.pbrc.hawaii.edu/allen/).