154 INITIATIVE IN EVOLUTION 



H. Wilder Harris. I refer to it here because the disappearance 

 of the rough, plain, nodular or corrugated epidermis in mammals 

 is coincident with increasing activity and intelligence in forms who 

 employ or acquire a more delicate sense of touch in their hands 

 and feet. The cruder response of structure to stimuli of friction 

 and pressure, evident in the lower forms, is abandoned in the higher, 

 as tactile delicacy in prehension comes more into play. Here, 

 for example, may be a subtle case of the co-operation of the mould 

 and sieve in action. 



From this lemur-level the degree of development in the Primate 

 palm and sole rises and falls, but always advances through the 

 lemur oidea, monkeys and anthropoid apes to man. No attempt 

 at the tracing of the lineage is made here, and from the present 

 limited point of view little remains to be said about different 

 Primates. Only two of those examined will be briefly referred to, 

 the slow loris and man. 



The slow loris shares with many monkeys and apes a very soft 

 moist skin of the palm and sole, and in this and other refinements 

 of this region it is much beyond many more intelligent, active 

 and higher Primates. I have never had social intercourse with a 

 loris, but I have shaken the friendly little hand of a chimpanzee 

 with a combination of pleasure, mild shock and perhaps memories 

 of my own palms in the more nervous moments of early life. It is 

 a strange, cool, soft and damp surface, but the sensation conveyed 

 by the skin of a loris lately dead show that in life it is a wonderfully 

 sensitive and tender structure. The whole of the palm and sole 

 is covered with well -developed patterns of papillary ridges especially 

 on the palmar and plantar pads . No trace of old-fashioned nodules, 

 scales or corrugation is to be found. The structures due to stimuli 

 of friction and pressure in its ancestors have disappeared for ever 

 from this specialised and small group, and we may fairly hold, in 

 accordance with the law of conservation of energy, that the past is 

 somehow enwrapped in the present in the strange hands and feet 

 of the loris. The adaptations of the hand and foot of the loris 

 are most obviously now of value to it in its wary and dangerous 

 life in the branches of trees, but are equally unfitted for that higher 

 life which, in his case, consists in going lower down, on the ground. 

 The extraordinary deliberate life of the loris has been often described. 

 As he moves from place to place on a branch, fixing one limb before 

 he moves another, much as we do in going up a ladder, he is subjected 

 much to the stimuli of pressure, but hardly at all to those of friction. 

 He sets us a good example of leaving nothing to chance. Thus 

 his soft sensitive skin suits well his mode of progression, but he 



