CUTANEOUS SENSATIONS 



637 



heat sense is affected by a lesion of the cord all forms and all degrees of the 

 sensation are affected in like measure, and the same applies to the sensations 

 of cold. 



The conduction paths of these different sensations in the cord are shown 

 in Fig. 176 on page 358. 



, 



THE HISTOLOGICAL CHARACTER OF THE ELEMENTS 

 INVOLVED IN CUTANEOUS SENSATIONS 



A very large number of different forms of sensory nerve .endings have 

 been described in relation to the skin. Their exact allocation among the 

 different cutaneous senses presents considerable difficulties. 



FIG. 316. Skin end organs and the sensations which they arouse. 



As regards touch, two kinds of elements are probably involved. In 

 the first place, the most sensitive tactile apparatus are the follicles of the 

 short hairs. Around these follicles we find a sheaf of nerve fibres, some 

 of which end in the hair papilla and others form a ring near the level of the 

 openings of the sebaceous glands. The other tactile end organ is Meissner's 

 corpuscle. The distribution of these in the skin is not however dissimilar 

 to that of the power of discrimination, with which they may be specially 



