A section through the coccyx and S-1 and S-2 spinal ganglia.
Observe:
1. The termination of the primitive filum terminale dorsal to the coccyx.
2. The termination of the sympathetic trunks in Section 36 in the ganglion impar ventral to the coccyx.
3. The three layers of the sacral part of the spinal cord.
Keywords: S-1 spinal ganglion, S-2 spinal ganglion, coccyx, ependymal layer, ganglion impar, gluteus maximus muscle, mantle layer, marginal layer, primitive filum terminale, sacrum, transversopinal muscle group, vertebral canal
Source: Atlas of Human Embryos.