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 *scribed. It may be regarded as the form from which all the other special senses have developed, certain portions of the body having become more sensitive than others to certain vibrations, as the eye to those of light. The internal organs probably have little sense of touch.

—Meissner's corpuscle from man; ×750. (Böhm, Davidoff, and Huber.)

Touch is useful only within arm's reach but there gives one a sense of space that sight does not give. It is practically determined by the touch corpuscles, which are found in the skin over almost the entire body, though they are more numerous in some places than in others, the distribution of the corpuscles determining the sensitiveness of the skin. These touch corpuscles are protoplasmic bodies containing nuclei, about which are entwined filaments from the cutaneous nerves. Where the corpuscles are absent the filaments of the cutaneous nerves themselves play an important part. The finger tips have a very delicate sense of touch and the tip of the tongue is the most sensitive part of the body. Hence spaces in the mouth seem larger than elsewhere. By the