2364. The bones of the sex are the feet with their appurtenances, such as the pelvis with the lumbar, sacral and coccygeal vertebræ. The muscles, as well as the nerves, are self-understood. But of these we will speak in the sequel.
2365. All organs, which are purely animal, are penetrated or traversed by the nervous system, just as the lower systems are by the tegumentary formation. No higher organ is the wholly pure evolution of one system, but the systems ever combine with each other; and this combination, when individually represented, constitutes the organ.
2366. Organ is distinguished from system in not pursuing its course through the whole body, nor consisting simply of one and the same mass, but by its occupying a definite part of the body and being composed of several systems.
2367. Every organ has therefore a special and specific function also.
2368. The systems of animal life divide only into two kinds of organs, into those of sensation and those of motion, into the solar and planetary, or central and peripheric.
a. MOTOR ORGANS.
2369. Bone and muscle are not societies, but only poles of one system. There is therefore no mere bony organ, and no mere muscular organ. Meanwhile we will here regard them in particular or "per se."
1. Osseous Organs.