Abstract
The structure of narcissus mosaic virus (NMV) particles and its protein polymers have been re-examined. The virus particle contains 44 coat protein subunits in five turns of its helix and has a mol. wt. of about 36 x 106. Its protein forms stacked discs or rings at pH 5 which, with time, are replaced by two-start helices with 26 subunits in three turns or nine in one.