Cytochemical studies on the chromatin elimination in solenobia (Lepidoptera)

Summary The chemical nature of the elimination chromatin in the first maturation division ofSolenobia was investigated with the Feulgen reaction, by staining with methyl green-pyronin. with toluidine blue before and after treatment with ribonuclease and cold perchloric acid, with the Hotchkiss periodic acid-Schiff test, and the Millon reaction.The Feulgen reaction and Hotchkiss test for polysaccharides turned out, to be negative while the tests for ribonucleic acid and protein were positive. The elimination chromatin is therefore essentially ribonucleoprotein.The elimination process is considered to be one way by which chromosomes rich in ribonucleoprotein typically present in metabolically active cells, are stripping themselves from material that may have become superfluous. Such visible shedding of material from chromosomes, though less spectacular than in the maturation division of eggs in Lepidoptera and few other insects, may be more common than is generally thought and it is suggested that the interzonal fibers found in many mitoses fall into this category.