Figure 432 from Chapter 16 (Cytoplasmic matrix and cytoskeleton) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. Smooth muscle of mouse epididymal duct. The area within the rectangle is shown at higher magnification in the accompanying image CIL:36065 from this image group, highlighting the presence of actin filaments. A PDF copy of the accompanying chapter is available on the ASCB’s BioEDUCATE website.