DERMATOGLYPHICS IN PRIMATES 177 



fields conform closely to the basic plan. Galago presents the 

 highest pattern intensity of all prosimians, and the excess of 

 palm over sole in pattern intensity is small; differences of 

 intensity among the configurational groups and between right 

 and left members are slight. 



Nycticebus is definitely less primitive than Galago in the 

 following respects : the extent of formed ridges is increased 

 to the point of completeness in the case of the sole and in some 

 palms (which otherwise lack complete ridges only in a very 

 small area) ; pattern intensity is lessened; there is increased 

 difference between the pattern intensities of the palm and sole ; 

 increased regional differences in pattern intensity occur. 



The attempt to place Daubentonia, Tarsius, Perodicticus 

 and Lemur in a sequence of decreasing primitiveness might 

 lead to a spurious order. Lemur, for example, is not as ad- 

 vanced as Nycticebus with regard to the extent of completely 

 ridged skin; but paradoxically there is a greater advance as 

 measured by the distinction of the palm and sole in pattern 

 intensity, and resemblance to the configurational topography 

 of the simians is striking. 



Perodicticus may be assigned an intermediate position be- 

 tween Galago and Nycticebus. The ridged area, as compared 

 to Galago is greater in expanse, and the configurational fields 

 closely approach the appearance of Nycticebus. Further com- 

 parisons are not feasible because of the availability of only 

 a single individual. 



The placing of Tarsius presents a problem. The dermato- 

 glyphics, primitive in view of the large expanse of ridge- 

 less skin, are advanced in the modifications brought about by 

 fusion of pads and configurational areas, and in regional 

 disparities in pattern intensity. On the basis of pattern in- 

 tensity and according to the interpretation which is applied 

 elsewhere, Tarsius would be described as advanced also in 

 possessing a low pattern intensity, indeed the lowest of any 

 primate. The qualities of the pads and configurations lead 

 inescapably to the impression that Tarsius represents a unique 

 departure from the characteristics of all other primates. 



