MONSTROSITIES 295 



perfect (note this) that it escapes detection unless the fingers are 

 actually counted ; occasionally there are several supernumerary 

 digits, but usually only one, making the total number six. This 

 one may be attached to the inner or outer margin of the hand, re- 

 presenting either a thumb or little finger, the latter being the more 

 frequent. Supernumerary digits are more common on the hands 

 than on the feet, but generally both hands and both feet are 

 similarly affected.' 



Mr. Darwin adds that 'the presence of a greater number of 

 digits than five is a great anomaly, for this number is not normally 

 exceeded by any existing mammal, bird, or reptile. Nevertheless, 

 supernumerary digits are strongly inherited ; they have been trans- 

 mitted through five generations, and, in some cases, after disappear- 

 ing for one, two, or even three generations, have reappeared through 

 reversion. These facts are rendered, as Professor Huxley has 

 observed, more remarkable from its being known in most cases that 

 the affected person has not married one similarly affected.' 



In such cases, the child of the fifth generation would have only 

 one-thirty-second part of the blood of his first sex-digitated ancestor. 

 Other cases are rendered remarkable by the affection gathering 

 force, as Dr. Struthers has shown, in each generation, though in each 

 the affected person married one not affected ; l moreover, such 

 additional digits are often amputated soon after birth, and can 

 seldom have been strengthened by use. Dr. Struthers gives the 

 following instance : * In the first generation an additional digit 

 appeared on one hand ; in the second on both hands ; in the third, 

 three brothers had both hands, and one of the brothers a foot, 

 affected ; in the fourth generation all four limbs were affected.' 

 Dr. Struthers however asserts that cases of non-inheritance are 

 much more frequent than cases of inheritance. 



1 Note this. The affection gathers force even when diluted ivith normal blood. 



