PALM AND SOLE STUDIES. 

 VIII. OCCURRENCE OF PRIMITIVE PATTERNS (WHORLS). l 



H. H. WILDER, 

 SMITH COLLEGE. 



INTRODUCTION. 



If we are correct in our morphological interpretation of the 

 friction-skin patterns of the human palms and soles (Miss 

 Whipple, 1904; H. H. Wilder, 1916) considering them the 

 vestiges of the former walking-pads, we should expect to find upon 

 each of these surfaces the typical set of eleven patterns, each in its 

 proper topographical position. These are, in either hand or foot, 



Five Apical or terminal, upon the balls of the terminal phalanges 



of the five digits, fingers or toes. 

 Four I nter digital , upon the more distal portion of palm or sole, 



proximal to the bases of the separate digits, and corre- 

 sponding to the intervals between them. 

 One Thenar, upon the thenar eminence, i.e., the more proximal 



portion of the palm or sole, on the side of digit I., radial or 



tibial. 

 One Hypothenar, upon the hypothenar eminence, i.e., the more 



proximal portion of the palm or sole, on the side of digit V., 



ulnar or fibular. 



All eleven of these may be represented in a single palm or sole 

 (H. H. Wilder, 1908, Figs. I and 2), but this is the greatest of 

 rarities, only two cases, and these duplicate twins, have been thus 

 far recorded. In the overwhelming majority of individuals the 

 palm and sole patterns present but a small part of the complete 

 set, and exhibit these in every stage of degeneracy down to a 

 slight convergence of ridges in one spot, which indicates the final 

 disappearance of the last triradius. Some of these are much 

 more constant than others, as illustrated by the five apical 

 patterns, the "finger-prints" of the professional dactyloscopists, 



1 Contributions from the department of Zoology, Smith College, No. 130. 



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