40^ 



Duplicate Twins and Double Monsters 



The other difference, that of the right thumbs, presents a somewhat 

 greater difficulty, but morphologically the patterns are very similar and 

 in order to convert the pattern in x into that in // all that is needed is 

 to complete the breaking down of the weaker triradius (the right in tlio 

 print), which has already begun, leaving all other ridges exactly as at 

 present. 



The reversal of index patterns as seen in the right hands is a good 

 typical example of that frequently recurring phenomenon, and seems to 

 occur with too great frequency (four cases out of nine) to be disposed 

 of simply as a lack of correspondence like the rest. The other cases, as 

 has been shown, are usually or always those of transition patterns not 

 really unlike morphologically, but in this case one pattern is the exact 

 symmetrical equivalent of the other, and hardly capable of l)ecoming 

 identical by anything less than a complete rearrangement of the entire 

 pattern. These reversed patterns may be better studied in the enlarged 

 figures of their cores, represented in (a) of Fig. 10. 



As in the case of the palms there is little or no attempt at corre- 

 spondence in the minutise, as may well be seen by applying a reading 

 glass to the cores of the patterns in Plate B, or by a study of the 



enlarged cores of Fig. 10, which show those 

 of the indices, middle and ring fingers of the 

 tw^o right hands. The various ulnar loops, 

 for example, show several types of Galton's 

 " Secondary Classification " without any cor- 

 respondence between the two individuals; 

 thus the single rod expressed by the descrip- 

 tive suffix " i,'' appears in .r-left, middle 

 finger, in y-leit, thumb and middle fingers, 

 and in a;-right, middle and little fingers. 

 The eyed rod, suffix " i," appears in x, right 

 index, and in conjunction with a single rod 

 in .r, left thumb. The staple, sufiix " c," 

 appears 'n avleft, little finger, in ?/-left, little 

 and ring fingers, in .T-left, middle and little 

 fingers, and in //-right, little finger. In all 

 this there is some little correspondence, as in 

 Fig. 10 b, but that it is probal)ly a coinci- 

 dence a])pears from the lack of correspond- 

 ence in the other minutias, as is easily seen 

 by a more complete scrutiny of the figure just referred to. 



In close connection with the present subject come investigations of 



X 



Fig. 10. Cores of fing-er pat- 

 terns from set No. I. Compare 

 with Plate B. 



(a) Rifrhf indices. Note the 

 Reveri^al. 



(b) Right middle fing-ers. 



(c) Right ring fingers. 



