A relatively simple technic giving consistent results has been evolved from Mayer's mucihematein technic1 by substituting hematoxylin for hematein and omitting the nitric acid. The hematoxylin is oxidized with sodium iodate (NaIO3). This modification is effective on the same types of mucin as Mayer's original mucihematein. With this modified technic, mucin stains a deep violet, cell nuclei pale gray blue, and connective tissue pale gray to colorless in tissues fixed in all the more common fixatives. The modified stain retains this selectivity for at least 200 days.