Whistler-derived electron densities in the equatorial plane have been compared with the plasmapause position as determined by the Explorer 45 double-probe experiment during times of relatively quiet magnetic activity. From periods where good coincidence of the data was obtained, the double-probe data saturation point (indicating the plasmapause) is estimated to have been in the vicinity of 60 el/cm3. By using this comparison the dayside plasmaphere was monitored over a 20-hour period on July 21 and 22, 1972, with two widely spaced whistler ground stations and Explorer 45. Irregularities in the dayside plasmasphere which appeared to be enhanced by dayside processes involving magnetic activity and/or micropulsations were seen during a small disturbance centered in this very quiet period.