

DISTINGUISHING IDENTICAL AND FRATERNAL TWINS 



411 



on the finger and palm prints of five pairs 

 of monozygotic and forty-two pairs of dizy- 

 gotic twins whose placentas had been ex- 

 amined at birth. They found that the cor- 

 responding fingers of identical twins are 

 usually very similar, to such an extent that 



; at least seven, and at most nine, fingers 

 have the same type of patterns, but at least 

 one finger shows dissimilarity. The palm 

 patterns of hands of identical twins show 

 even closer resemblance; the similarity of 

 the same side especially is very great. The 

 palms of the dizygotic twins, on the con- 

 trary, are never so much alike. Accord- 

 ingly he expressed his view that the 

 palm prints give the most reliable criterion, 

 next to the placenta, for identifying 

 monozygotic twins. 



Bonnevie (192.3, 192.4), in her studies on 

 finger prints, examined the degree of 

 similarity found between same-sex twins 

 with 16 pairs of presumably fraternal 

 and 15 pairs of presumably identical 

 twins as material. She estimated the 

 degree of similarity between each pair 

 according to her own scheme, and found 

 that the correlation of pattern-values 

 between fraternal twins is very similar to 

 that between ordinary brothers and sisters, 

 whereas the correlation between the 

 identical (?) twins is much higher, in fact 

 so much as to "fully equal and even 

 slightly exceed that found for the values 

 of right and left hands of identical twins, 

 or of single persons" (192.4, p. 100). 



Leven (192.4) studied the finger prints 



1 of 2.3 pairs of same-sex twins including 

 15 pairs of presumably monozygotic and 

 8 pairs of presumably dizygotic twins. 



I Much more difference, in the type of 

 patterns, as well as in the number of 

 ridges and in other details, was found 

 among the latter than among the former 

 kind of twins. 



Lauterbach (192.5), in his study on ziz 

 pairs of twins, consisting of 149 pairs of 



same-sex, and 63 pairs of different-sex 

 twins, examined the palm patterns. 

 Special attention was given to the palm 

 patterns of the twins showing symmetry 

 reversal in handedness and in the whorl of 

 the head hair. His conclusion was that 

 "palm patterns afford no certain means of 

 identifying monozygotic twins. Unlike- 

 sex pairs of twins may show identity 

 of palm patterns and reveal symmetry 

 reversal" (p. 567). 



Montgomery (192.6) worked on the 

 sole patterns of 57 pairs of same-sex, and 

 30 pairs of different-sex twins. He con- 

 cluded that "the presence of identical 

 patterns on the soles of a pair of twins 

 might point to their monozygotic origin, 

 but, as Newman states, their absence does 

 not disprove it" (p. Z99). 



Kuragami (192.6) examined finger-prints 

 of 15 pairs of same-sex twins and 5 pairs 

 of different-sex twins, and found, among 

 other things,, that in two pairs of the same- 

 sex twins the ridgecount of the prints gave 

 precisely the same value. 



Obonai (192.6) carried on a psycho- 

 logical and anthropological study on some 

 zoo pairs of twins. He also examined 

 the finger prints of these twins, and called 

 attention to the fact that some pairs of 

 same-sex twins which would be taken as 

 identical judging by their resemblance in 

 physiognomy and in physical and psychi- 

 cal characteristics, may have very unlike 

 finger patterns. 



Kishi (19x7) collected finger prints of 

 60 sets of twins including 49 pairs of 

 same-sex and 11 pairs of different-sex 

 twins, and has found, among other things, 

 that the finger prints of different-sex 

 twins are more variable than those of 

 same-sex twins. 



Apart from works dealing with only a 

 few pairs of twins, the above is, I believe, 

 a nearly comprehensive review of the 

 literature relating to the finger, palm, or 



