[Calcium localization in the degenerating myotubes of developing skeletal muscle in the chick embryo]

Ca-accumulating formations found in degenerating myotubes of chick embryo by pyroantimonate technique have been identified as membrane bound bodies in the material fixed routinely for electron microscopy. These bodies seem to represent initial stages of a lipid degeneration of membranous structures. It is assumed that calcification of single degenerating subcellular structures may limit spreading necrosis over the whole cell.