diagrams of muscles and motor axons

This pair of diagrams shows the groups of muscles thought to be innervated by the various nerve branches in different colors: ISN muscles (1,2,3,49,10,11,18,19,20), green; SNa muscles (5,8,21-24), red; SNb muscles (6,7,12,13,30,14,28), yellow; SNc/d muscles (15-17, 25-27, 29), blue. The organization of the muscles is the same as in the previous image (muscles alone), with the views from the exterior and interior shown. The nerves are indicated (from left): tn, blackish/gray; ISN, black; SNb, blue; SNa, maroon; SNd, green; SNc, blue-gray. The dotted lines indicate regions where the motor axons travel under the muscles shown. We do not know that the side branch that we see on SNc at early 17 actually reaches muscles 26 and 27.

There are some problems with this way of depicting the relationships of the nerves and muscles, since the muscles themselves are in multiple focal planes, and the representation in this diagram is not 100% accurate. Nevertheless, it does convey some aspects of the actual pathways taken by the nerves.

To early 17 brightfield embryo (this is the next link in the tour).

To diagram of muscles.

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