Negative staining and cellulose microfibril size

SUMMARY Reason is given for the belief that an overlapping of images ensures a gross underestimate of cellulose microfibril width in plant cell walls observed both in section and negatively stained. Both theory and optical simulation of the electron‐microscope situation suggest that the error involves a factor of at least two or three times. These, and other considerations render doubtful the existence of elementary microfibrils as components of the broad (c. 20 nm) microfibrils of some seaweeds.