A statistical study of narrowband transverse 0.1- to 4.0-magnetic pulsations, essentially Pc 1--2 (0.1-5.0 Hz), occurring from L=3.5 to L=9, ‖MLAT‖7 have not previously been discussed and are found to exhibit remarkable polarization behavior. The A.M. events have the highest X observed in the data base, with X averaging 0.4 to 0.5, but most remarkably, they are linearly polarized at all magnetic latitudes sampled. Given the high normalized frequency, the equatorial linear polarization of the A.M. events cannot be explained in terms of a crossover from left- to right-hand polarization occurring during propagation from low to high magnetic field strengths. Oblique propagation or the effects of multiple reflection through the wave growth region might lead to linear polarizations. The results suggest that a new examination of EMIC wave generation specifically addressing the properties of this A.M. population may be needed. ¿ American Geophysical Union 1992