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cited showing how these repulsions are frequently, if not 

 generally, hereditary. Although, therefore, the sense of 

 touch concerns physiology rather than pathology, there can 

 be no question that in the one as in the other, heredity 

 governs all the phenomena. 



The senses of taste and smell are so allied as to be 

 almost inseparable. Like the sense of touch, these latter 

 ones concern also physiology rather than pathology, but 

 where the phenomena are permanently involved in patho- 

 logical conditions, then heredity is the rule, as in those 

 which are purely physiological. The specific, as well as the 

 individual varieties of taste and smell, are alike transmissible. 

 I have elsewhere referred to the physiological phenomena, 

 which are undoubtedly hereditary ; but, for obvious reasons, 

 beyond the fact that every form and variety of the sensorial 

 development of smell and taste, whether congenital absence, 

 anaesthesia or hyperaesthesia, in every degree, are subject to 

 heredity, I cannot go. Purely pathological conditions of 

 the senses of smell and taste are so generally, merely of a 

 temporary character, that they cannot be regarded as trans- 

 missible, but in everything appertaining to the development 

 and degree of the senses themselves, heredity is distinctly 

 apparent, as indeed it would inevitably be pathologically, if 

 their functions required the exercise of special local organs, 

 as in the case of sight and hearing ; or if, in like manner, 

 they were subject to characteristic and definite diseases. 



From the foregoing observations it will be seen that in 

 relation to the sensorial qualities, heredity plays its part, 

 and exercises its influence, not only physiologically but 

 pathologically also. With regard to sight and hearing, we 

 have seen that not only the visual and acoustic abnormalities 

 and diseases are transmissible, but that, in the case of touch, 



