Two recent papers contain some erroneous results. In Fig. 6, on page 42, of “Computer simulation of flagellar movement IX. Oscillation and symmetry breaking in a model for short flagella and nodal cilia”, Cell Motility and the Cytoskeleton 60: 35-47, the results shown by solid circles and solid line are incorrect. Similar results are shown in Figs. 4 and 5 of “Symmetry breaking in a model for nodal cilia”, AIP Conference Proceedings 755: 107-116. These results were obtained with models for nodal cilia containing a high value of elastic shear resistance. However, the method used for computing the elastic shear moment acting on an outer doublet resulted in contamination by the shear experienced by an adjacent doublet. If a method that avoids this contamination is used, the results obtained with models containing elastic shear resistance are similar to those obtained with models that do not have elastic shear resistance, such as the results shown by open circles and dashed lines in Fig. 6 of the first paper.

    With this correction, the only methods that were found to give an effective control of circling direction involve unidirectional information transfer from doublet to doublet around the axoneme. Simply twisting the axoneme by dynein moment does not appear to have a strong enough effect to be a realistic method for ensuring counterclockwise circling.