early 17 SNa, focal plane 3

This focal plane shows the proximal SNa (same 2 segments as last focal plane). The bifurcation is indicated. SNa is slightly posterior to SNb in each of the segments; this is generally the case, but the exact position is not highly stereotyped. This focal plane shows the distal end of the anterior branch, which innervates muscle 24.

To early 17 SNc/d

To early 17 SNa focal plane 2

To early 17 brightfield

To diagram of muscles.

To 2nd diagram (muscles and motor axons).

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