SOLE PATTERNS OF TWINS. 



295 



right and both left patterns must have the same formula, and 

 (2) there must be no marked differences in the patterns even 

 if they have the same formula. As space does not permit a more 

 detailed description of the Wilder method of classification, the 

 reader is referred to his writings on the subject. Fig. I illustrates 



FIG. i. Twins 7-8. Formula: 



A2idd 



Some of the lines have been inked in 



A6dd 

 order that the patterns might be more readily seen. 



a set of identical patterns. On close examination the similarity 

 of the patterns of each individual is striking. In this series 

 13 sets (14.94 P er cent.) are identical (Table II.), and all except 



