The classical continuous spectrum of fluid flow found by C.M. Case [Phys. Fluids 3, 143 (1960) ] is contained in the Alfven and slow continua of magnetohydrodynamics (MHD). Contrary to several statements in the literature, most recently by S.N. Bhattacharyya and A. Bhattacharjee [Phys. Plasmas 4, 3744 (1997) ], there are no additional flow continua in MHD. Additional Eulerian continuum modes do exist in both fluids and plasmas, but they only involve non-Lagrangian perturbations of the density or the entropy, not of the pressure and the magnetic field. (C) 2004 American Institute of Physics.