This preliminary study visualizes the glottal excitation in a temporally highly resolved estimate of the first formant. Instantaneous estimates of the frequency and bandwidth of the first formant closely follow the electroglottographic contour. This is demonstrated for modal, breathy, and hoarse phonation of an [a:] produced by one male and one female speaker. The temporally highly resolved formant contours show glottal features such as the different durations of the open phase and fundamental frequency and/or amplitude perturbations of the vocal fold vibration. Keywords: linear prediction, electroglottography