DEKMATOGLYPHICS IN PRIMATES 161 



CRITERIA OF PRIMITIVENESS AND MODIFICATION 



The "primitive" configurational field. The question of what 

 constitutes the primitive state of an individual configurational 

 field naturally arises in any comparative approach. Sequences 

 of pattern types may be traced in continuous series from 

 a well developed concentric whorl through steps of transition 

 to a loop pattern, which in turn may be traced to complete loss 

 of pattern character in the state of an open field. Such series 

 of steps, it is obvious, are revealed not in the ontogeny of the 

 single configuration but rather in a selected collection of pat- 

 terns. One might read the scale of pattern development from 

 either direction, were it not for the intimate associations of 

 pads and patterns. The primitive pattern may be justly re- 

 garded, following Whipple and Wilder, as the type which is 

 associated with that form of pad which has most primitive 

 character. This reference to conditions of pads suggests that, 

 of all configuration types, whorls might be rightly viewed as 

 primitive (though, as noted just below and in the later dis- 

 cussion of the affinities of prosimians, this position can not be 

 maintained without reservation). Whorls occur on pads which 

 are prominently elevated as more or less pointed mounds. 

 The occurrence of a whorl, however, is not necessarily de- 

 pendent upon the presence of such a mound in the adult. The 

 pads may persist in the fetus only long enough to condition 

 whorl development, later subsiding into a relief which is not 

 sensibly different from that of other slight elevations bearing 

 configurations of quite different types. In some non-human 

 primates which have pads that persist in what is essentially 

 an approximation of the fetal condition (Pithecus and pre- 

 sumably all other forms which exhibit conspicuous pads in 

 the adult), an actual correlation between the character of the 

 pad reliefs and grades of pattern development is observable in 

 the adult ; but in other forms, as in man and great apes, ' ' primi- 

 tive" whorls and pattern types closely resembling them may 

 occur in the absence of reliefs presenting primitive modelling. 

 It is therefore the fetal pads which provide a key to inter- 

 pretation, since the configurations are determined in their 



