142 CHARLES MIDLO AND HAROLD CUMMINS 



graphic relations of these areas are difficult to reconcile with 

 any mechanism such as that which is assumed to be responsible 

 for the usual axial reduction in pattern intensity in non- 

 human forms. If these two areas be set aside as localizations 

 of minimal intensity which are not influenced by relationships 

 with the axis, then the two remaining interdigital areas are 

 significantly aligned in reference to the anatomical axis. In 

 the palm and sole alike the area having the lesser value, inter- 

 digital III in the palm or II in the sole, lies in the axis. We 

 regard this relationship of pattern intensity to the anatomical 

 axis as of the same fundamental meaning as other expressions 

 of structure and variation centering about it. The differences 

 of these expressions in the hand and foot of man include such 

 diverse manifestations as digital lengths, localization of 

 syndactyly, distribution of hair on the digits and distribution 

 of dermatoglyphic patterns on fingers and toes. 



Except in some prosimians, in which the longest digit of the 

 hand is the fourth, digit III is the longest in primates ( Schultz, 

 '26; Midlo, '34). As for the toes of primates, the third is 

 the longest as a rule. In some prosimians and New World 

 monkeys the fourth toe may equal the third or even exceed 

 it in length, while in man the longest toe is the second or the 

 first (Schultz, '26). It will be evident that in primates gener- 

 ally the hand and foot present the longest digit in relation to 

 the anatomical axis. Since in most forms this axis is in line 

 with digit III in both hand and foot, the shifting tibialward 

 of maximal toe length in man is of special interest in showing 

 that there may be some significant association between maxi- 

 mal digital length and the axis. That such is the case is sug- 

 gested by the relationship to the axis of other features. 

 Before considering these, further attention should be given 

 the principle of serial comparison which is illustrated in 

 figure 599. In a typical primate, as just pointed out, maximal 

 digital lengths occur in numerically corresponding digits of 

 hand and foot. A graphic alignment of the human digits in 

 serial order (fig. 599A), adjusted so that digits of greatest 

 length coincide, leaves isolated the thumb and little toe, which 



