| Abstract: | The pigmented cells in Malpighian tubules of Drosophila melanogaster contain yellow globules which are blackened by osmium tetroxide. Permanent preparations of the tubules showing pigmentation can thus be made. Following prestaining acid hydrolysis, osmium-fixed tubules can be stained with orcein. For observations on pigment distribution and Feulgen-DNA content in the same preparation, tubules are fixed in mercuric chloride. Color remains visible for several hours in unfixed tubules mounted in modified buffered Ringer solution. |
