The _black-headed lemur_ is the lowest Primate examined and it is characterised by highly developed patterns of ridges on the palm and sole, and these are interspersed with nodules on the regions less exposed to pressure. The complexity of the patterns of another, the _ring-tailed lemur_, is greater still. Now these nodules are distinguished from the rough undifferentiated nodules of lower forms, such as the Canadian _tree-porcupine_, and from the scales in others. When examined with a lens the separate nodules show small groups of papillary ridges two, three or four on each nodule, arranged in a direction parallel to those of neighbouring nodules. They are in fact papillary ridges in embryo, and shortly above this lemur-stage in the ascent of animal life they are merged into papillary ridges in patterns. All this is well told at length by Dr. and Mrs. 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 _lemuroidea_, _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.