Now this very extraordinary and rare auditory memory was developed in an altogether abrupt way. Inaudi, the son of poor peasants of Piedmont, passed the first years of his life as a shepherd. At the age of six his wonderful faculty of calculating figures appeared. He did not know at this time how to read or to write. At eleven years of age he astonished the members of the Anthropological Society of Paris by his phenomenal memory, and it was only much later, at the age of twenty, that he learnt to read and write. Neither of the parents of Inaudi had shown in the slightest degree a calculating faculty like that of little Jacques. It must then be admitted that it was developed as suddenly as the new qualities in the Evening Primrose that we have already mentioned. The first men, also, were probably ingenious children, born of anthropoid parents. This hypothesis very well explains the fact that man is more like the fœtus and the young of anthropoid apes than the adult animals, and exhibits only a trace of many organs which are much more developed in simian species. A very distinguished German anatomist, Wiedersheim,[66] has given in a pamphlet a _resumé_ of our actual knowledge of the organs of man from the point of view of their descent. He has found fifteen organs which show in the human species a considerable advance on those of anthropoid apes. The chief of these are the lower limb, well adapted for a constant erect carriage of the body; the strengthening of the pelvis and of the sacrum, as well as the broadening of the more slender pelvis of the female; the curvature of the lumbar part of the vertebral column; the development of the buttocks and of the calves; the difference of certain muscles of the face; the nose; certain strands from the brain to the spinal cord; the occipital lobe of the brain; the greater development of the cerebral cortex, and, lastly, the considerable differentiation of the muscles of the larynx which permit speech. But besides these progressive organs, Wiedersheim has counted seventeen decaying organs, still able to fulfil their physiological function in a more or less incomplete manner (amongst these are the decadent muscles of the leg and foot; the eleventh and twelfth pairs of ribs, the toes, the cæcum, etc.), and not less than one hundred and seven rudimentary organs which serve no useful physiological purpose (to this category belong the coccyx—the vestige of a tail—the thirteenth pair of ribs in the adult, the muscles of the ear, the vermiform appendage, etc.). We have already shown in the preceding chapter the great importance of rudimentary organs as aids to the tracing of the genealogy of organisms. These organs, useless at present, are the vestiges of similar but more developed organs, which fulfilled a useful function in our ancestors.