136 CHARLES MIDLO AND HAROLD CUMMINS 



have yielded little result. For example, in the three pronounced 

 brachiators, Ateles, Hylobates and Pongo, there is agreement 

 in possession of greater intensity in the hypothenar group 

 of the palm than in the thenar, yet some non-brachiating forms 

 display a like tendency though of lesser degree, and, to render 

 the problem still more perplexing, comparisons of the foot 

 are even less consistent. It is quite possible, of course, that 

 an approach to this question on the basis of exacting analysis 

 of varying methods of grasping and progression would reveal 

 correlations which we have failed to find. 



The next appropriate comparison involves the correspond- 

 ing groups of palm and sole, the thenar group of the palm 

 to be compared with the thenar group of the sole, and the 

 hypothenar groups of the two members to be treated in the 

 same manner. Since we are dealing with relative intensities, 

 a representation of the thenar comparisons, as shown in 

 figure 600, forms a mirror image of the relative intensities of 

 the hypothenar group, which is therefore omitted to gain 

 simplicity of the graph. The graph represents differences in 

 relative intensity, hence zero differences and differences so 

 small as to be negligible indicate likeness in intensity of the 

 corresponding groups of hand and foot. In this as in other 

 comparisons of pattern intensity the prosimian genera are 

 found to be widely variable. The most marked unlikenesses 

 between corresponding groups in palm and sole occur in 

 Tarsius, Hylobates and Homo. This is taken to indicate that 

 significant differences between corresponding groups of palm 

 and sole occur in at least these three genera. 



To supplement the foregoing comparisons of the thenar 

 and hypothenar groups in the same member and of correspond- 

 ing groups in palm and sole, comparisons are next drawn 

 with the purpose of determining relationships between the 

 thenar group of the palm and the hypothenar group of the 

 sole and the converse relationship between palmar hypothenar 

 and plantar thenar groups. 



The differences in relative intensities are plotted in figure 

 600, where it will be noted that these two cross comparisons 



