Abstract
Carnoy-fixed paraffin sections from adult rat pancreas, ileum (in mitosis), thyroid gland, mammary gland, and ovaries were stained by gallocyanine-chromalum previously descr. by the author. By varying the pH, the basophilic material was stained progressively and in some cases selectively. The selectively stained structures seem to be nucleo proteins. Because of the progressive nature of the staining, the basophilia could be estimated quantitatively.