SOCIETY OF THE UNIVERSITY OF ABERDEEJx 7 . 7 



on the right hand the percentage of 72 is found. On this finger 

 Gallon's maximum is 76 per cent., but he obtained the greatest 

 number of loops on the little finger, where the remarkable total of 90 

 per cent, was reached. 



Whorls are most common on the thumbs and most rare on the 

 middle fingers. 



Although in the two foregoing tables the similarity in percentages 

 between the same digits is marked, the difference in frequency on 

 thumb, forefinger and middle finger is very great. Thus on the right 

 thumb arches are 3'2 per cent., on the forefinger they are as many as 

 18 '4 per cent., and on the middle finger their occurrence is 9 - 6 per 

 cent. 



The forefinger is peculiar in the frequency with which the direc- 

 tion of the slopes of the loops differs from that which is most frequent 

 on the other digits. A loop necessarily has a slope since it is formed 

 of ridges opening downwards on one or the other side of the finger. 

 If it opens to the outer side or thumb side of the hand it is called a 

 radial slope, if towards the inner side an ulnar slope. 



Galton found that the radial slope was rare on the middle finger, 

 but that it occurred on the forefinger two-thirds as frequently as the 

 ulnar slope. This ratio he proved for separate forefingers. In the 

 foregoing statistics of 52 - 4 per cent, of loops on the right forefinger, 

 24'4 per cent, were radial and 28 per cent, were ulnar. Of 52 per 

 cent, on the left forefinger, 16'4 per cent, were radial and 35 '6 per 

 cent, were ulnar. In neither case does Galton's rule hold ; but add 

 together the radials of the two hands and likewise the ulnars and the 

 percentages now are : 20'4 per cent, are radials and 31 '8 per cent, are 

 ulnars. This gives a result similar to Galton's. 



Now consider the tendency of digits to resemble one another in 

 their various combinations. Take them two at a time to determine 

 the frequency with which both members of the various couplets show 

 the same class of pattern. First take the digits of the same name ; 



