Muscular stimulus, [248].

Muscular stimulus and contraction, to illustrate, [261].

Muscular tissue, kinds of, [243], [244].

Nails, [267].
Care of, [276].

Nasal duct, [383].

Neck exercise, [328].

Nerve cells, [281], [282].

Nerve fibers, [282], [293], [294].

Nerve path, diagram of, [286].

Nerve pathways, to demonstrate, [322].