1. The glycerine in Mayer's glycerine and albumen serves no useful purpose.
2. If about one-half of the haematoxylin in such solutions as those of Heidenhain and Ehrlich be oxidized by sodium iodate, the dyes are ready for use the moment they have been made up and also keep well.
3. In using crystal violet for staining chromosomes, it is best to fix the dye by an aqueous (instead of the usual alcoholic) solution of iodine.