426 Palms and Soles 



STUDY or THKEE CASES OF SO-CALLED " IDENTICAL TWINS," whicll wiU 



be seen to have an important bearing upon the structure of the egg- 

 nucleus and kindred biological problems ; and (3) the use of the main 



LINES OF the palms AND SOLES FOR PERSONAL IDENTIFICATION, espe- 

 cially in criminal records; a method much more practical than the use 

 of the finger-prints alone, as advocated by Galton, and more simple 

 and rapid than the Bertillon system now in extensive use. 



The follovring tabulation of the above results will present them more 

 clearly and at the same time serve as a Table of Contents for the body 

 of the paper: 



T. General MorpJwlogy. — (a) Method of interpretation, (b) Nomen- 

 clature, (c) Variation in the lines and areas, (d) Occurrence of pat- 

 terns, (e) Races and sexes. 



II. Palms and Soles in Identical Tivins. — (a) Actual condition as seen 

 by study of three cases, (b) Theoretical bearing. 



III. Use as Means of Personal Identification. — (a) Palms and soles vs. 

 finger-tijDs. (b) Comparison with other systems, (c) Uses. 



I. General Morphology. 



a. Method of Interpretation. — In my paper of 1897, referred to in the 

 introduction, I state among others the following conclusions. The 

 italics, as used here, are for the purpose of the present paper, and were 

 not so used in the original: 



" III. In some Primates, including man, the mounds suffer a more 

 or less complete reduction, so that often the epidermic figure, or 

 ' centre,' is alone left to designate the spot. In cases of extreme reduc- 

 tion, the epidermic centre may also disappear. 



" lY. In man the apical centres on the finger tips are fairly constant, 

 that form designated by Galton as a " simple arch " being the most 

 reduced. The palmar, thenar, and hypotlienar centres are of uncertain 

 occurrence." 



It was after writing this that I began the study of as many human 

 palms and soles as possible, for the purpose of ascertaining the average 

 degree of reduction of the " centres," and the amount of atavism, and 

 for a time looked only for the centres themselves, i. e. for at least some 

 loop or other disturbance of the papillary ridges marking the core of 

 a pattern. In this way I found that such patterns were relatively a 

 little more frequent in the sole than in the ]ialm; that in the former, 

 for example, a thenar pattern was almost constant; that, in the latter, 

 one of the three palmar patterns was usually indicated, and so on; but 



