Figure 3 of Biswas, Mol Vis 2010; 16:2328-2341.

Figure 3. SEM of ball-and-sockets in different cortical regions of monkey lens (20 year old). A: Superficial cortical fibers (approximately 100 μm from the surface), numerous ball-and-sockets are distributed on the long side of fiber cells. B: Intermediate cortical fibers (approximately 300 μm from the surface), a large number of ball-and-sockets are found on the long side of fiber cells. In this region, many protrusions (p) are also distributed along the corners of cortical fiber cells. C: However, in the deeper cortex (approximately 500 μm from the surface), ball-and-sockets display smaller number and size with degenerating appearance. The scale bars indicate 1 μm.