[Individual anatomic variability of Forel's field H].

The investigation was performed in serial frontal sections of 100 preparations of the diencephalon and midbrain made 1 mm from one another. The shape of Forel H field was found to be very variable, changing from the rectangular to triangular shape in pararubralparts, and from oval to semioval-in prerubral parts. The size and position of Forel H field proved to change in relation to intracerebral reference points: posterior comissure, medial and intercomissural planes used in stereotaxical technique.