RESULTS OF AN EXPERIMENT WHERE CHEMICALS WERE SPRAYED ONTO A LATENT FINGERPRINT AREA SHOWED THAT AMINO ACIDS, PEPTIDES, PROTEINS, AND UREA ARE OFTEN PRESENT IN LATENT FINGERPRINT RESIDUE THROUGH CONTACT WITH FRICTION RIDGES. CURRENTLY, NINHYDRIN IS USED TO PRODUCE VISUALIZATION OF LATENT PRINTS, ALTHOUGH OBJECTS WITH BACKGROUND COLOR WILL NOT PRODUCE SUFFICIENT CONTRAST. ALTHOUGH, IN THE EXPERIMENT, FLUORESCAMINE AND O-PHTHALALDEHYDE PROVED MORE SENSITIVE THAN NINHYDRIN AND GAVE BETTER CONTRAST ON DARK AND MULTICOLORED SURFACES, THEY WERE FOUND TO BE LESS STABLE. TABULAR DATA ARE INCLUDED. (MJW)