front matter 1

Top View Side View

AB

CD

EF

White matter

outlined

Gray matter

outlined

Central canal

(defines midlline)

Medial motor columns

11

Figure 14. The thoracic region in specimen M2050 (GW8.5, CR 36 mm). The individual sections in this model are diagrammed in Figure 11 and include
sections 1225-1884. The reconstructed length in the specimen is 6.99 mm after fi xation. Panels A, C, and E show the model from the top front, panels B,
D, and F from the upper right side. Panels A and B show both the white matter (outlined outer transparent envelope) and gray matter (inner transparent
envelope) around the central canal (gray-white solid) and the medial motor columns (cyan). Panels C and D show the only gray matter (outlined outer
transparent envelope) around the central canal and the medial motor columns. Panels E and F show the central canal and the medial motor columns
alone. This region of the spinal cord is distinguished from other regions by having only one motor column ( 1 ) that probably innervates axial muscles
associated with the thoracic vertebrae, rib cage and dorsal abdominal wall.

GW8.5, CR 36 mm, M2050 FIGURE 14