Organs of Touch.
2448. Where, however, the skin has attained to a higher grade of formation, or where it has combined with higher systems, there also will the sense of feeling be supplied by the former.
2449. The combination of the integument with the osseous and muscular system, and with a nervous system of its own, takes place in the limbs. Since the motor members are only a liberated thorax, so no other sense can belong to them but that of feeling, which the thorax previously possessed.
2450. But these sensitive organs are moved, and therefore voluntary organs, digits, or former branchiæ. Moveable or voluntary organs of feeling are called tactile organs. The feeling of the motor members is touch.
2451. The highest feeling necessarily consists in touching, because it has in that become active, while before it was only passive.
2452. In the situation of the sensitive papillæ, the origin of the digits from respiratory organs admits of being still recognized. They are arranged in spiral lines upon the points of the fingers.
2453. The sexual organs belong as tegumentary developments to the sense of feeling. There is no special sexual sense.
2. Intestinal Sense.
2454. Opposite to the general feeling or the integument, the function of the intestine is evolved. In the trunk it is simply busied with its own processes; when it first mounts or ascends into the head, it becomes subordinated to the nervous action.
2455. The combination of the intestine with bones, muscles and peculiar nerves, is presented in the tongue. This is the sensitive organ of the intestine.