18 CHARLES MIDLO AND HAROLD CUMMINS 



importance in reflecting the factors of differential growth 

 which are responsible for the production of patterns. The 

 combination of findings in the fetus and in the adult admits 

 the construction of a comprehensive morphologic plan which 

 comprises, in both palm and sole, seven marginally placed 

 elevations of relatively constant occurrence. These pads, and 

 their abbreviated designations, are: 



H d , distal element of the hypothenar 



H p , proximal element of the hypothenar 



Th, thenar (in the sole having two elements, proximal and 

 distal Th p and Th d ) 



the interdiital series. 





IV 



The locations of these pads correspond to configurationa! areas 

 of the same names, as shown in figures 3 and 4. 



As will be detailed in a following section, the morphologic 

 plan is subject to considerable modification in individual 

 genera. Among the modifications there should be noted 

 especially the tendency of adjoining pads to fuse. II'' and II P , 

 for example, may be represented by a single eminence, H. 

 Likewise, Th and I frequently are combined in one elevation. 



Except in connection with elements of the hypothenar, no 

 alterations of previous nomenclature of the primary border 

 pads have been made. In his discussion of the fetal history 

 of volar pads, Cummins ('29, fig. 1) distinguished two hypo- 

 thenar pad elements, proximal and distal. What was then 

 considered the proximal component alone is itself subdivided 

 in the palm, as later recognized by the same author ('35b). 

 The elements which we designate herein as H' 1 and H p are these 

 subdivisions, while the fetal pad which Cummins had regarded 

 as the distal hypothenar we now assign (as IV U ) to the series 

 of five subsidiary pads next to be mentioned. The palmar pad 

 which we name H p is termed by Schlaginhaufen the carpal 

 pad. In explanation of this altered terminology, it should be 

 stated that the new designations appear to be more in keeping 



