166 CHARLES MIDLO AND HAROLD CUMMINS 



is impracticable to reduce the conformities and non-conformi- 

 ties to a quantitative basis, their comparisons utilize general 

 impressions gained by inspection. 



(2) In each genus the average pattern intensities of each 

 of the seven configurational areas listed above, added to give 

 the value known as total intensity, provide a second measure 

 of primitiveness. High pattern intensities indicate not only 

 that the several configurational fields are likely to be indi- 

 vidually present in conformity to the basic plan, but also that 

 the areas tend to bear patterns which are either primitive or 

 but little advanced. Intergeneric comparisons may thus be 

 made of the whole palm and sole, separately or combined. 

 When pattern intensity is used in gauging primitiveness, and 

 this applies not only to the total intensities but also to various 

 other considerations of this measure, it must be understood 

 that pattern intensities fluctuate in accord with membral and 

 regional specializations. Because this is true, man, for ex- 

 ample, is far from being as nearly primitive with respect to 

 pattern intensities as in the conformity to the morphologic 

 plan of configurations. Indeed, man is to be ranked among 

 the highly specialized primates, along with Tarsius, Ateles 

 and Hylobates each having its own kind of specialization, 

 in the instance of Hylobates, at least, representing departures 

 from primitiveness which are carried further than in man and 

 in directions which are in part peculiar to the genus. 



(3) On the assumption that the theoretically most primitive 

 state would take the form of highly developed patterns in all 

 seven of the configurational areas in both palm and sole, com- 

 parisons of pattern intensity are designed to disclose evidences 

 of regional unlikenesses. Two modes of regional grouping- 

 are chosen, the first being based upon relationships to the 

 anatomical axis. Alongside the axis are the thenar group of 

 configurational areas (Th, I and II) and the hypothenar 

 group (H p , H d and IV). In a theoretically unspecialized 

 member the two groups should be equal, each having an in- 

 tensity of 3.00. With unequal specialization in these outer 

 and inner regions of the same member, the intensities would 



