"To 100 cc. of 45% glacial acetic acid add 10 g. of carmine; dissolve by heating and allow to come to a boil; cool and filter; remove the filter paper from the funnel and spread it out flat to dry. The filtrate is Schneider''s aceto-carmine and may be saved for the uses indicated for this stain. When the residue left on the filter paper is dry, remove it as carefully as possible. It may be used at once or placed in a tightly closed container for future use. The staining soln. is made up the same as Mayer''s carmalum, substituting the acidified carmine descr. above for carminic acid. Acidified carmine 1 g., alum 10 g., distilled water 200 cc. The ingredients are mixed and dissolved with heat; when completely dissolved and cooled, filter the mixture and add a crystal of thymol to prevent mold growth. If correctly used this stain gives a deep rose red color to the principal organs of trematodes. It is purely a nuclear stain, and consequently there is no diffuse stain in the cytoplasm, making the organs stand out in the practically transparent body.".