  From TESS photometry, 493 mid- to late-B stars with high frequencies (Maia
variables) have been identified. The distribution of projected rotational
velocities shows that the rotation rates of Maia variables are no different
from those of SPB stars. Moreover, many Maia stars pulsate with frequencies
exceeding 60 c/d. Rapid rotation is ruled out as a possible factor in
understanding the Maia variables. There is clearly a serious problem with
current pulsational models. Not only are the models unable to account for the
Maia stars, but they also fail to account for the fact that SPB and gamma Dor
variables form one continuous instability strip from the cool end of the delta
Sct region to the hot end of the beta Cep instability strip. Likewise, there is
continuity between the distributions of delta Sct, Maia, and beta Cep
variables. In fact, Maia stars seem to be an extension of delta Sct stars to
the mid-B type. These observations suggest an interplay between multiple
driving mechanisms rather than separate dominant mechanisms for each
variability group.
