There are few differences between this ISN and those in the early 17 images. Note muscles 21-23, visible in this focal plan; these are innervated by SNa. To late 16 ISN, detail of distal end To early 17 ISN, focal plane 1 To early 17 ISN, focal plane 2 To late 16 brightfield To diagram of muscles. To 2nd diagram (muscles and motor axons). Back to table of contents	(click on image to enlarge)