1. A fingerprint minutia correcting system for correcting an input fingerprint image extracted from an object to produce a corrected fingerprint signal representative of a corrected fingerprint image, said input fingerprint image including minutiae and ridges, said fingerprint minutia correction system comprising: means for extracting said minutiae from said input fingerprint image to produce minutia data signals representative of said minutiae; means for determining said ridges by using said minutia data signals; means for calculating an average distance between two adjacent ones of said determined ridges; display means for visually displaying said minutia data signals on said input fingerprint image; pointing means operable in cooperation with said display means for indicating specific locations on said display means; correcting means for correcting said minutia data signals on said displaying means by indicating each location on said display means by the use of said pointing means to leave real minutia data signals together with said fingerprint image on said display means and to obtain said corrected fingerprint image on said display means, said real minutia data signals being representative of real minutiae; list formulating means for formulating a minutia list in relation to said real minutiae and said determined ridges by the use of said corrected fingerprint image; means for storing said minutia list as said corrected fingerprint signal; said list formulating means comprising: means for automatically indicating an objective one of said real minutiae together with an adjacent one of said real minutiae; means for detecting locations of said objective and said adjacent ones of the real minutiae; means for calculating estimated ridge numbers between said objective and said adjacent ones of the real minutiae, using said average distance between two adjacent ones of said determined ridges, after detection of said locations of the objective and the adjacent ones of the real minutiae; visual display means for displaying said estimated ridge numbers on said displaying means; correcting means for correcting said estimated ridge numbers into corrected ridge numbers when said estimated ridge numbers are wrong; and means for successively memorizing the locations and said corrected ridge numbers into said minutia list.