DERMATOGLYPHICS IN PRIMATES 139 



tensities of these three groups in most monkeys is therefore 

 a regular disto-proximal gradient. The prosimians, some 

 New World monkeys, great apes and man conform in general 

 to Old World monkeys only in that the distal group is char- 

 acteristically the one which shows the highest relative in- 

 tensity. Tarsius and Hylobates are the most conspicuous 

 exceptions, in having the proximal group much elevated in 

 pattern intensity and the distal group much reduced. In the 

 prosimians, except Tarsius, in Callithrichidae, Alouatta, great 

 apes and man the tendency is for the intermediate group to 

 present the lowest intensity and the proximal group to occupy 

 a middle place. 



Sole. The relative intensities of the three groups in most 

 genera conform to the disto-proximal gradient mentioned as 

 characteristic of the palms of most monkeys. The prosimian 

 genera are irregular with respect to this gradient. The only 

 monkeys presenting departures are Lagothrix, Cebus and 

 Pygathrix. In gibbon the great apes and man the seriation of 

 pattern intensities of the three groups is widely variable. In 

 Hylobates, exactly reproducing the condition in the palm, it 

 is the proximal group which has the highest intensity and the 

 distal group the lowest; this relative order occurs also in 

 Pan, and is closely approached in Gorilla. The order in Pongo 

 adheres to the general primate trend only insofar as it is the 

 distal group which has the maximum intensity ; the inter- 

 mediate group has by far the lowest intensity. The singular 

 position of man, where the intermediate group stands so far 

 above the other groups in pattern intensity, calls for reference 

 to the topographic distinctiveness of the hallucal pattern and 

 its possible lack of complete homology with the first inter- 

 digital patterns in other primates with which it is compared. 

 The hallucal pattern in man lies in transverse line with the 

 interdigital series and simulates them also with respect to 

 high pattern intensity. If this special feature be discounted, 

 the group intensities in man would compare much more closely 

 to those in Gorilla and Pan. It may be suggested that the 

 more common sequence, in which the distal, intermediate and 



