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of anaesthesia, that could form an exception to this rule." 

 The relative susceptibility and insusceptibility of some 

 individuals and families to tickling is well-known, and the 

 numerous idiosyncrasies as to contact with silk, cork, 

 woollen clothing, etc., need only be mentioned. These 

 are unquestionably hereditary. The hand itself the very 

 organ of touch is affected by heredity. For as Mr. 

 Spencer has observed : " Large hands are inherited by 

 men and women whose ancestors led laborious lives, and 

 men and women whose descent, for many generations, has 

 been from those unused to manual labour, commonly have 

 small hands." A predisposition to left-handedness is also 

 transmissible, as the writer can prove from the following 

 circumstances connected with his own family. For at least 

 four generations there has been a strong tendency to left- 

 handedness in each. Thus, my paternal grandfather, who 

 was an excellent sportsman and a first-rate marksman, shot 

 from the left shoulder, as I do myself ! In each of the four 

 generations, some member, or members of the family, 

 showed the strongest tendency to left-handedness ; and 

 during my childhood my left arm was bound up for weeks, 

 but all to no purpose : Natura non nisi parendo vindtur I 

 Still more curious is the fact that my sisters' children 

 manifest the same tendency. 



With regard to sight "the most intellectual of all the 

 senses" its varieties depend on mechanical causes, and on 

 anaesthesia or hyperaesthesia of the nervous apparatus of 

 vision, and all anomalies are hereditarily transmissible. 

 Amongst those peculiarities dependent on mechanical causes 

 may be included strabismus, myopia, and presbyopia : these 

 are all markedly hereditary. Ribot says : " Anaesthesia of 

 the nerves of sight is transmissible in all its grades, and in 



