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I. Are similar epidermic markings found upon the hands and 
feet of other Primates? 
II. Do they correspond to anything upon the feet of other 
Mammals? 
When these questions are answered it will be seen that others 
are involved, such as the origin of epidermic folds in general; the 
causes, mechanical or otherwise, which have produced the contortions 
in certain particular places, and the study of special patterns for the 
purpose of reducing them all to a common type. The facts presented 
in this paper have reference mainly to the first two questions, which 
will be considered with reference to the hand alone, after which, com- 
parison with the foot will be taken up as a separate topic. 
I. Material for this subject has not been easy to obtain, and my 
conclusions are based upon the study of one Inuus and three Cebi. 
The Inuus furnished the most useful hand, a sketch of which is 
given in Fig. 1. Here it will be seen that the regions of disturbance 
in the course of the epidermic folds are much more numerous than 
in man, being located on the palm of the hand as well as upon the 
finger-tips. Each region of disturbance is marked by a very definite 
centre, and these centres are absolutely the same in each hand and 
have the same location. They may be named as follows: 
1 thenar, 
1 hypothenar, 
1 accessory hypothenar, 
3 palmar (radial, median and ulnar), 
5 apical. 
Comparing the hands of the three Cebi with this form, taken as 
a diagram, I found the following differences. The accessory hypothenar 
failed in four cases and was obscurely indicated in two. In both hands 
of one specimen the ulnar palmar lacked a definite centre but here, 
as in the two cases showing indications of an accessory hypothenar 
centre, an elevated mound showed the location for it. 
Besides the centres enumerated in the above table there were 
seen both in Inuus and Cebus small and often obscurely indicated 
centres upon the first and second rows of phalanges, but they are 
very uncertain and sporadic in their occurrence and seldom involve 
more than one or two folds. Those in the right hand of Inuus are 
given in the figure, but they are too uncertain to be considered here. 
We may thus not only affirmatively answer the first 
question proposed, but we may add to the apical mark- 
ings on the fingers a set of definitely located centres 
1 A 
