Harris Ha\rt.liorne Wilder 



441 



TABLE II. 



No. 



Degree of 



physical 



resemblance. 



Correspondence of 

 palmar formulas. 



I. I Identical.* 

 II. Identical.* 



III. Identical. + 

 V. Identical. t 



Identical.* 

 Identical. "I" 

 Xll.f Identical.-)- 



XIV. Identical.! 



IX. 

 XI. 



Complete. 



One difTerence 

 in left. 



Extent of bilateral 

 symmetry in the 

 palmar formulae. 



9 Complete. 



^ Two diflferences 

 in left. 



XV. 



Identical. 



Complete.;]: 



Complete. 



One difference 

 in left. 



One difference 

 in left.+ 



9 Complete. 



Complete. 



Complete with the 

 exception just 

 noted. 



None. 



Complete with the 

 exceptions just 

 noted. 



None. 



Complete. 



Complete with the 

 exception just 

 noted. 



Complete with the 

 exception just 

 noted. 



None. 



Reversal of index 

 pattern. 



Rights. 

 Lefts. 



None. 

 Lefts. 



None. 

 None. 

 None. 



Indices show two al- 

 ternating patterns, 

 i. e., X- left =2/- 

 right, and ?/- left 

 — X- right. 



Right. 



* Decision rests upon personal inspection. 



t Decision rests upon testimony of others, all reliable sources. 



; In addition a carpal difference not counted because of reasons above stated. 



g The two boys alone from the set of triplets. 



A complete bilateral symmetry in the case of duplicate twins calls 

 for a double correspondence, i. e., four hands with the same formula, or, 

 in cases where there is a point of difference, three hands alike and the 

 fourth also corresponding save in the point noted; and yet this difficult 

 requisite is fulfilled in six out of the nine sets, while in the other three 

 there is no attempt at bilateral correspondence. This seems to show 

 that a bilaterality in the case of true duplicates is to be looked for, 

 although it is not a prerequisite. 



The occasional reversal of an index pattern is, perhaps, the most sin- 

 gular phenomenon yet observed, but it occurs too often to be a coinci- 

 dence (4 out of 9, with a strange interrelationship in a fifth). The table 

 shows that this reversal bears no necessary relationship to the bilaterality, 

 since it occurs in Nc XV, in which there is no bilateral symmetry, and, 

 on the other hand, is entirely absent in XI and XII, in which a com- 

 plete bilaterality exists. In its commonest form it consists of the re- 

 versal of a loop, which is ulnar in one individual and radial in the other. 



