The pars intermedia has fused with the pars nervosa and is not very evident in the human. Here we can see a region with numerous colloid cysts and small, lightly stained cells situated between the pars distalis and the pars nervosa. The nature of the colloid is not known. Determining which part of this region is pars intermedia and which is something else is difficult. Thus, you are not responsible for identifying cells in the pars intermedia.
Pars distalis .
In the pars distalis , many of the cells are rounded and their cytoplasmic granules stain red. These are the acidophils . The unstained cells, chromophobes , include both cells of several types with too few granules to stain. See also EM DEMO 4 and 5 for granule morphology, but remember immunocytochemistry would be required for definitive identification. You are responsible for understanding those techniques.