Stimulated by the recent proton study of Walker, Kivelson, and Schardt, I have made a detailed reexamination of the University of Iowa data on energetic electrons during a Pioneer 10 traversal of the plasma sheet in Jupiter's dawn magnetodisc at about 51 RJ (Jupiter equatorial radii) on 6--7 December 1973. The principal finding is that electrons of energy Ee>0.060 MeV provide only 3 (¿0.5) percent of the charged particle pressure required to explain the observed depression in the magnetic field at the center of the plasma sheet despite the fact that the intensity of such electrons is well correlated with the depression of the magnetic pressure throughout the sheet. The contribution of energetic protons to the particle pressure is reassessed in a subsequent paper by Goertz, Parish, Van Allen, and Schardt.