260 Form and folor in Nature. 



limitation and differentiation of their activities. Modern physiology 

 shows that the sense of touch, for example, is not a uniform thing in 

 all parts of the body that certain superficial areas respond more 

 promptly to sensations of heat, others to cold, others to titillations, 

 etc. The divisions between the senses are, perhaps, not so rigid as we 

 are disposed to think. It is possible that the sense of muscular con- 

 tractility that sense by means of which we are enabled to judge of 

 weight and resistance should be differentiated from the ordinary 

 tactile sense. As to what constituted the primitive mode of sense- 

 activity I should, perhaps, not agree wholly with either the lecturer or 

 Dr. Eccles. I can not think that the developed sense of touch, as we 

 understand it, existed in primitive organisms, or a distinct sense of 

 taste, either. The mode of perception of such organisms may, per- 

 haps, be best regarded as a vague, undifferentiated sense of feeling, 

 which combined the germinal forms of both taste and touch indeed, 

 of all the special senses. Binet regards sight as the earliest of the 

 special senses to be evolved. If this is the fact, it is somewhat re- 

 markable that it is still in some respects the most undeveloped and 

 defective. As to the order of their development, there seems to me to 

 be a wide range for speculation and hypothesis. It may be more cor- 

 rect to regard their evolution as in a large degree simultaneous. 



ME. POTTS, in reply, said that in the matter of the senses he had 

 used the term " sense of touch " as being the term of the simplest 

 character, intended to convey the idea of a general sensibility to im- 

 pressions which seemed to him nearer to our sense of touch than to 

 anything else. He did not intend to imply that the lowest organisms 

 possessed a developed tactile sense, such as the higher mammals now 

 exhibit, however. His paper had taken a form quite different from 

 that which he originally had in mind, and he was glad if it had proved 

 interesting and provocative of thought. 



